PHP Basic Algorithm: Exercises, Practice, Solution
This resource offers a total of 680 PHP Basic Algorithm problems for practice. It includes 136 main exercises, each accompanied by solutions, detailed explanations, and four related problems.
[An Editor is available at the bottom of the page to write and execute the scripts.]
1. Sum Triple if Same
Write a PHP program to compute the sum of the two given integer values. If the two values are the same, then returns triple their sum.
Sample Input
1, 2
3, 2
2, 2
Sample Output:
3
5
12
Click me to see the sample solution
2. Absolute Difference with Triple
Write a PHP program to get the absolute difference between n and 51. If n is greater than 51 return triple the absolute difference.
Sample Input:
53
30
51
Sample Output:
6
21
0
Click me to see the sample solution
3. Check for 30 or Sum is 30
Write a PHP program to check two given integers, and return true if one of them is 30 or if their sum is 30.
Sample Input:
30, 0
25, 5
20, 30
20, 25
Sample Output:
bool(true)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
4. Within 10 of 100 or 200
Write a PHP program to check a given integer and return true if it is within 10 of 100 or 200.
Sample Input:
103
90
89
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
5. Prepend 'if' to String if Missing
Write a PHP program to create a new string where 'if' is added to the front of a given string. If the string already begins with 'if', return the string unchanged.
Sample Input:
"if else"
"else"
"if"
Sample Output:
if else
if else
if
Click me to see the sample solution
6. Remove Character at Given Position
Write a PHP program to remove the character in a given position of a given string. The given position will be in the range 0..string length -1 inclusive.
Sample Input:
"Python", 1
"Python", o
"Python", 4
Sample Output:
Pthon
ython
Pythn
Click me to see the sample solution
7. Exchange First and Last Characters
Write a PHP program to exchange the first and last characters in a given string and return the new string.
Sample Input:
"abcd"
"a"
"xy"
Sample output:
dbca
a
yx
Click me to see the sample solution
8. Four Copies of First 2 Characters
Write a PHP program to create a new string which is 4 copies of the 2 front characters of a given string. If the given string length is less than 2 return the original string.
Sample Input:
"C Sharp"
"JS"
"a"
Sample Output:
C C C C
JSJSJSJS
a
Click me to see the sample solution
9. Add Last Character at Front and Back
Write a PHP program to create a new string with the last char added at the front and back of a given string of length 1 or more.
Sample Input:
"Red"
"Green"
"1"
Sample Output:
dRedd
nGreenn
111
Click me to see the sample solution
10. Check Multiple of 3 or 7
Write a PHP program to check if a given positive number is a multiple of 3 or a multiple of 7.
Sample Input
3
14
12
37
Sample Output:
bool(true)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
11. Add First 3 Characters Front and Back
Write a PHP program to create a new string taking the first 3 characters of a given string and return the string with the 3 characters added at both the front and back. If the given string length is less than 3, use whatever characters are there.
Sample Input:
"Python"
"JS"
"Code"
Sample Output:
PytPythonPyt
JSJSJS
CodCodeCod
Click me to see the sample solution
12. Check if String Starts with "C#"
Write a PHP program to check if a given string starts with 'C#' or not.
Sample Input:
"PHP"
"C#"
"C++"
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
13. Temperature Extremes Check
Write a PHP program to check if one given temperatures is less than 0 and the other is greater than 100.
Sample Input:
120, -1
-1, 120
2, 120
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
14. Integers in Range 100..200
Write a PHP program to check two given integers whether either of them is in the range 100..200 inclusive.
Sample Input:
100, 199
250, 300
105, 190
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution
15. Three Integers in Range 20..50
Write a PHP program to check whether three given integer values are in the range 20..50 inclusive. Return true if 1 or more of them are in the said range otherwise false.
Sample Input:
11, 20, 12
30, 30, 17
25, 35, 50
15, 12, 8
Sample Output:
bool(true)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
16. Two Integers in Range 20..50
Write a PHP program to check whether two given integer values are in the range 20..50 inclusive. Return true if one or other is in the said range otherwise false.
Sample Input:
20, 84
14, 50
11, 45
25, 40
10, 19
Sample Output:
bool(true)
bool(true)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
17. Remove "yt" from Index 1
Write a PHP program to check if a string 'yt' appears at index 1 in a given string. If it appears return a string without 'yt' otherwise return the original string.
Sample Input:
"Python"
"ytade"
"jsues"
Sample Output:
Phon
ytade
jsues
Click me to see the sample solution
18. Largest of Three Integers
Write a PHP program to check the largest number among three given integers.
Sample Input:
1,2,3
1,3,2
1,1,1
1,2,2
Sample Output:
3
3
1
2
Click me to see the sample solution
19. Nearest to 100 Check
Write a PHP program to check which number nearest to the value 100 among two given integers. Return 0 if the two numbers are equal.
Sample Input:
78, 95
95, 95
99, 70
Sample Output:
95
0
99
Click me to see the sample solution
20. Check Integers in Range 40..50 or 50..60
Write a PHP program to check whether two given integers are in the range 40..50 inclusive, or they are both in the range 50..60 inclusive.
Sample Input:
78, 95
25, 35
40, 50
55, 60
Sample Output:
bool(false)
bool(false)
bool(true)
bool(true)
Click me to see the sample solution
21. Largest in Range 20..30
Write a PHP program to find the larger value from two positive integer values that is in the range 20..30 inclusive, or return 0 if neither is in that range.
Sample Input:
78, 95
20, 30
21, 25
28, 28
Sample Output:
0
30
25
28
Click me to see the sample solution
22. Count 'z' Characters Between 2 and 4
Write a PHP program to check if a given string contains between 2 and 4 'z' character.
Sample Input:
"frizz"
"zane"
"Zazz"
"false"
Sample Output:
bool(true)
bool(false)
bool(true)
bool(false)
Click me to see the sample solution
23. Same Last Digit Check
Write a PHP program to check if two given non-negative integers have the same last digit.
Sample Input:
123, 456
12, 512
7, 87
12, 45
Sample Output:
bool(false)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
24. Uppercase Last 3 Characters of String
Write a PHP program to convert the last 3 characters of a given string in upper case. If the length of the string has less than 3 then uppercase all the characters.
Sample Input:
"Python"
"Javascript"
"js"
"PHP"
Sample Output:
PytHON
JavascrIPT
JS
PHP
Click me to see the sample solution
25. n Copies of a Given String
Write a PHP program to create a new string which is n (non-negative integer) copies of a given string.
Sample Input:
"JS", 2
"JS", 3
"JS", 1
Sample Output:
JSJS
JSJSJS
JS
Click me to see the sample solution
26. n Copies of First 3 Characters
Write a PHP program to create a new string which is n (non-negative integer) copies of the the first 3 characters of a given string. If the length of the given string is less than 3 then return n copies of the string.
Sample Input:
"Python", 2
"Python", 3
"JS", 3
Sample Output:
PytPyt
PytPytPyt
JSJSJS
Click me to see the sample solution
27. Count "aa" Substring Occurrences
Write a PHP program to count the string "aa" in a given string and assume "aaa" contains two "aa".
Sample Input:
"bbaaccaag"
"jjkiaaasew"
"JSaaakoiaa"
Sample Output:
2
2
3
Click me to see the sample solution
28. First "a" Followed Immediately by Another "a"
Write a PHP program to check if the first appearance of "a" in a given string is immediately followed by another "a".
Sample Input:
"caabb"
"babaaba"
"aaaaa"
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution
29. Every Other Character String
Write a PHP program to create a new string made of every other character starting with the first from a given string.
Sample Input:
"Python"
"PHP"
"JS"
Sample Output:
Pto
PP
J
Click me to see the sample solution
30. Build Progressive String Pattern
Write a PHP program to create a string like "aababcabcd" from a given string "abcd".
Sample Input:
"abcd"
"abc"
"a"
Sample Output:
aababcabcd
aababc
a
Click me to see the sample solution
31. Count Substring Occurrences Excluding End
Write a PHP program to count a substring of length 2 appears in a given string and also as the last 2 characters of the string. Do not count the end substring.
Sample Input:
"abcdsab"
"abcdabab"
"abcabdabab"
"abcabd"
Sample Output:
1
2
3
0
Click me to see the sample solution
32. Specified Number in Array Check
Write a PHP program to check a specified number is present in a given array of integers.
Sample Input:
{1,2,9,3}, 3
{1,2,2,3}, 2
{1,2,2,3}, 9
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
33. First Four Elements Array Element Match
Write a PHP program to check if one of the first 4 elements in an array of integers is equal to a given element.
Sample Input:
{1,2,9,3}, 3
{1,2,3,4,5,6}, 2
{1,2,2,3}, 9
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
34. Check for Sequence 1,2,3 in Array
Write a PHP program to check whether the sequence of numbers 1, 2, 3 appears in a given array of integers somewhere.
Sample Input:
{1,1,2,3,1}
{1,1,2,4,1}
{1,1,2,1,2,3}
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution
35. Compare Strings for Matching 2-Character Substrings
Write a PHP program to compare two given strings and return the number of the positions where they contain the same length 2 substring.
Sample Input:
"abcdefgh", "abijsklm"
"abcde", "osuefrcd"
"pqrstuvwx", "pqkdiewx"
Sample Output:
1
1
2
Click me to see the sample solution
36. New String from Specific Indexes
Write a PHP program to create a new string of the characters at indexes 0,1,4,5,8,9 ... from a given string.
Sample Input:
"Python"
"JavaScript"
"HTML"
Sample Output:
Pyon
JaScpt
HT
Click me to see the sample solution
37. Count Adjacent 5's with 6 Variation
Write a PHP program to count the number of two 5's are next to each other in an array of integers. Also count the situation where the second 5 is actually a 6.
Sample Input:
{ 5, 5, 2 }
{ 5, 5, 2, 5, 5 }
{ 5, 6, 2, 9}
Sample Output:
1
2
1
Click me to see the sample solution
38. Detect Triple Consecutive Occurrence
Write a PHP program to check if a triple is presents in an array of integers or not. If a value appears three times in a row in an array it is called a triple.
Sample Input:
{ 1, 1, 2, 2, 1 }
{ 1, 1, 2, 1, 2, 3 }
{ 1, 1, 1, 2, 2, 2, 1 }
Sample Output:
bool(false)
bool(false)
bool(true)
Click me to see the sample solution
39. Sum with Conditional Range Return 30
Write a PHP program to compute the sum of the two given integers. If the sum is in the range 10..20 inclusive return 30.
Sample Input:
12, 17
2, 17
22, 17
20, 0
Sample Output:
29
30
39
30
Click me to see the sample solution
40. Check for 5, Sum or Difference Equals 5
Write a PHP program that accept two integers and return true if either one is 5 or their sum or difference is 5.
Sample Input:
5, 4
4, 3
1, 4
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution
41. Multiple of 13 or One More Than Multiple
Write a PHP program to test if a given non-negative number is a multiple of 13 or it is one more than a multiple of 13.
Sample Input:
13
14
27
41
Sample Output:
bool(true)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
42. Multiple of 3 or 7 but Not Both
Write a PHP program to check if a given non-negative given number is a multiple of 3 or 7, but not both.
Sample Input:
3
7
21
Sample Output:
int(1)
int(1)
int(0)
Click me to see the sample solution
43. Within 2 of a Multiple of 10
Write a PHP program to check if a given number is within 2 of a multiple of 10.
Sample Input:
3
7
8
21
Sample Output:
bool(false)
bool(false)
bool(true)
bool(true)
Click me to see the sample solution
44. Sum with Special Range Override (10..20?18)
Write a PHP program to compute the sum of the two given integers. If one of the given integer value is in the range 10..20 inclusive return 18.
Sample Input:
3, 7
10, 11
10, 20
21, 220
Sample Output:
10
18
18
241
Click me to see the sample solution
45. FizzBuzz String Start with F and/or End with B
Write a PHP program to check whether a given string starts with "F" or ends with "B". If the string starts with "F" return "Fizz" and return "Buzz" if it ends with "B" If the string starts with "F" and ends with "B" return "FizzBuzz". In other cases return the original string.
Sample Input:
"FizzBuzz"
"Fizz"
"Buzz"
"Founder"
Sample Output:
Fizz
Fizz
Buzz
Fizz
Click me to see the sample solution
46. Two Integers Sum to Third Check
Write a PHP program to check if it is possible to add two integers to get the third integer from three given integers.
Sample Input:
1, 2, 3
4, 5, 6
-1, 1, 0
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution
47. Increasing Order Check for x,y,z
Write a PHP program to check if y is greater than x, and z is greater than y from three given integers x,y,z.
Sample Input:
1, 2, 3
4, 5, 6
-1, 1, 0
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
48. Strict Increasing Order, Allow Equality Option
Write a PHP program to check if three given numbers are in strict increasing order, such as 4 7 15, or 45, 56, 67, but not 4 ,5, 8 or 6, 6, 8.However,if a fourth parameter is true, equality is allowed, such as 6, 6, 8 or 7, 7, 7.
Sample Input:
1, 2, 3, false
1, 2, 3, true
10, 2, 30, false
10, 10, 30, true
Sample Output:
bool(true)
bool(true)
bool(false)
bool(true)
Click me to see the sample solution
49. Same Rightmost Digit Among Integers
Write a PHP program to check if two or more non-negative given integers have the same rightmost digit.
Sample Input:
11, 21, 31
11, 22, 31
11, 22, 33
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
50. Check if One Integer is 20 or More Less Than Another
Write a PHP program to check three given integers and return true if one of them is 20 or more less than one of the others.
Sample Input:
11, 21, 31
11, 22, 31
10, 20, 15
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
51. Larger with Remainder Rule
Write a PHP program to find the larger from two given integers. However if the two integers have the same remainder when divided by 7, then the return the smaller integer. If the two integers are the same, return 0.
Sample Input:
11, 21
11, 20
10, 10
Sample Output:
21
20
0
Click me to see the sample solution
52. Shared Digit in Two Integers
Write a PHP program to check two given integers, each in the range 10..99. Return true if a digit appears in both numbers, such as the 3 in 13 and 33.
Sample Input:
11, 21
11, 20
10, 10
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution
53. Sum with Digit-Length Constraint
Write a PHP program to compute the sum of two given non-negative integers x and y as long as the sum has the same number of digits as x. If the sum has more digits than x then return x without y.
Sample Input:
4, 5
7, 4
10, 10
Sample Output:
9
7
20
Click me to see the sample solution
54. Sum of Three with Duplicate Override
Write a PHP program to compute the sum of three given integers. If the two values are same return the third value.
Sample Input:
4, 5, 7
7, 4, 12
10, 10, 12
12, 12, 18
Sample Output:
16
23
12
18
Click me to see the sample solution
55. Sum Excluding 13 and Right Side
Write a PHP program to compute the sum of the three integers. If one of the values is 13 then do not count it and its right towards the sum.
Sample Input:
4, 5, 7
7, 4, 12
10, 13, 12
13, 12, 18
Sample Output:
16
23
10
0
Click me to see the sample solution
56. Sum with Range Nullification Except 13/17
Write a PHP program to compute the sum of the three given integers. However, if any of the values is in the range 10..20 inclusive then that value counts as 0, except 13 and 17.
Sample Input:
4, 5, 7
7, 4, 12
10, 13, 12
17, 12, 18
Sample Output:
16
11
13
17
Click me to see the sample solution
57. Nearest to 13 Without Overrun
Write a PHP program to check two given integers and return the value whichever value is nearest to 13 without going over. Return 0 if both numbers go over.
Sample Input:
4, 5
7, 12
10, 13
17, 33
Sample Output:
5
12
13
0
Click me to see the sample solution
58. Equal Differences in Three Integers
Write a PHP program to check three given integers (small, medium and large) and return true if the difference between small and medium and the difference between medium and large is same.
Sample Input:
4, 5, 6
7, 12, 13
-1, 0, 1
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution
59. String Pattern: s1s2s2s1
Write a PHP program to create a new string using two given strings s1, s2, the format of the new string will be s1s2s2s1.
Sample Input:
"Hi", "Hello"
"whats", "app"
Sample Output:
HiHelloHelloHi
whatsappappwhats
Click me to see the sample solution
60. Insert String into Middle
Write a PHP program to insert a given string into middle of the another given string of length 4.
Sample Input:
"[[]]","Hello"
"(())", "Hi"
Sample Output:
[[Hello]]
((Hi))
Click me to see the sample solution
61. Three Copies of Last Two Characters
Write a PHP program to create a new string using three copies of the last two character of a given string of length atleast two.
Sample Input:
"Hello"
"Hi"
Sample Output:
lololo
HiHiHi
Click me to see the sample solution
62. First Two Characters Extraction
Write a PHP program to create a new string using first two characters of a given string. If the string length is less than 2 then return the original string.
Sample Input:
"Hello"
"Hi"
"H"
" "
Sample Output:
He
Hi
H
Click me to see the sample solution
63. First Half of Even-Length String
Write a PHP program to create a new string of the first half of a given string of even length.
Sample Input:
"Hello"
"Hi"
Sample Output:
He
H
Click me to see the sample solution
64. Remove First and Last Character
Write a PHP program to create a new string without the first and last character of a given string of length atleast two.
Sample Input:
"Hello"
"Hi"
"Python"
Sample Output:
ell
ytho
Click me to see the sample solution
65. Concat Shorter into Longer
Write a PHP program to create a new string from two given string one is shorter and another is longer. The format of the new string will be long string + short string + long string.
Sample Input:
"Hello", "Hi"
"JS", "Python"
Sample Output:
HelloHiHello
PythonJSPython
Click me to see the sample solution
66. Remove First Character from Both and Concat
Write a PHP program to concat two given string of length atleast 1, after removing their first character.
Sample Input:
"Hello", "Hi"
"JS", "Python"
Sample Output:
elloi
Sython
Click me to see the sample solution
67. Move First Two Characters to End
Write a PHP program to move the first two characters to the end of a given string of length at least two.
Sample Input:
"Hello"
"JS"
Sample Output:
lloHe
JS
Click me to see the sample solution
68. Move Last Two Characters to Start
Write a PHP program to move the last two characters to the start of a given string of length at least two.
Sample Input:
"Hello"
"JS"
Sample Output:
loHel
JS
Click me to see the sample solution
69. Remove First and Last Character (Any Length)
Write a PHP program to create a new string without the first and last character of a given string of any length.
Sample Input:
"Hello"
"JS"
''
Sample Output:
ell
Click me to see the sample solution
70. Middle Two Characters from Even-Length String
Write a PHP program to create a new string using the two middle characters of a given string of even length (at least 2).
Sample Input:
"Hell"
"JS"
Sample Output:
el
JS
Click me to see the sample solution
71. Check if String Ends with "on"
Write a PHP program to check if a given string ends with "on".
Sample Input:
"Hello"
"Python"
"on"
"o"
Sample Output:
string(2) "lo"
string(2) "on"
string(2) "on"
string(1) "o"
Click me to see the sample solution
72. Concat First and Last n Characters
Write a PHP program to create a new string using the first and last n characters from a given string of length at least n.
Sample Input:
"Hello", 1
"Python", 2
"on", 1
"o", 1
Sample Output:
Ho
Pyon
on
oo
Click me to see the sample solution
73. Substring of Length 2 at Given Index
Write a PHP program to create a new string of length 2 starting at the given index of a given string.
Sample Input:
"Hello", 1
"Python", 2
"on", 1
Sample Output:
el
th
on
Click me to see the sample solution
74. Middle 3 Characters from a String
Write a PHP program to create a new string taking 3 characters from the middle of a given string at least 3.
Sample Input:
"Hello"
"Python"
"abc"
Sample Output:
ell
yth
abc
Click me to see the sample solution
75. New String of Length 2 with Padding
Write a PHP program to create a new string of length 2, using first two characters of a given string. If the given string length is less than 2 use '#' as missing characters.
Sample Input:
"Hello"
"Python"
"a"
""
Sample Output:
He
Py
a#
#
Click me to see the sample solution
76. Concat First from One and Last from Another
Write a PHP program to create a new string taking the first character from a given string and the last character from another given string. If the length of any given string is 0, use '#' as its missing character.
Sample Input:
"Hello", "Hi"
"Python", "PHP"
"JS", "JS"
"Csharp", ""
Sample Output:
Hi
PP
JS
C#
Click me to see the sample solution
77. Concat Lowercase Strings and Omit Doubles
Write a PHP program to concat two given strings (lowercase). If there are any double character in new string then omit one character.
Sample Input:
"abc", "cat"
"python", "php"
"php", "php"
Sample Output:
abcat
PythonPHP
phphp
Click me to see the sample solution
78. Swap Last Two Characters in String
Write a PHP program to create a new string from a given string after swapping last two characters.
Sample Input:
"Hello"
"Python"
"PHP"
"JS"
"C"
Sample Output:
Helol
Pythno
PPH
SJ
C
Click me to see the sample solution
79. Check String Starts with 'abc' or 'xyz'
Write a PHP program to check if a given string begins with 'abc' or 'xyz'. If the string begins with 'abc' or 'xyz' return 'abc' or 'xyz' otherwise return the empty string.
Sample Input:
"abc"
"abcdef"
"C"
"xyz"
"xyzsder"
Sample Output:
abc
abc
xyz
xyz
Click me to see the sample solution
80. First Two and Last Two Characters Equality
Write a PHP program to check whether the first two characters and last two characters of a given string are same.
Sample Input:
"abab"
"abcdef"
"xyzsderxy"
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution
81. Concat with Removal for Different Lengths
Write a PHP program to concat two given strings. If the given strings have different length remove the characters from the longer string.
Sample Input:
"abc", "abcd"
"Python", "Python"
"JS", "Python"
Sample Output:
abcbcd
PythonPython
JSon
Click me to see the sample solution
82. Three Copies of First Two Characters
Write a PHP program to create a new string using 3 copies of the first 2 characters of a given string. If the length of the given string is less than 2 use the whole string.
Sample Input:
"abc"
"Python"
"J"
Sample Output:
ababab
PyPyPy
JJJ
Click me to see the sample solution
83. Remove First Two if Matching Last Two
Write a PHP program to create a new string from a given string. If the two characters of the given string from its beginning and end are same return the given string without the first two characters otherwise return the original string.
Sample Input:
"abcab"
"Python"
Sample Output:
cab
Python
Click me to see the sample solution
84. Remove 'a' from First and Last if Present
Write a PHP program to create a new string from a given string without the first and last character if the first or last characters are 'a' otherwise return the original given string.
Sample Input:
"abcab"
"python"
"abcda"
"jython"
Sample Output:
bcab
Python
bcd
jython
Click me to see the sample solution
85. Remove Leading 'a' or 'aa' from String
Write a PHP program to create a new string from a given string. If the first or first two characters is 'a', return the string without those 'a' characters otherwise return the original given string.
Sample Input:
"abcab"
"python"
"aacda"
"jython"
Sample Output:
bcab
Python
cda
jython
Click me to see the sample solution
86. Check if Array Starts or Ends with 10
Write a PHP program to check a given array of integers of length 1 or more and return true if 10 appears as either first or last element in the given array.
Sample Input:
{ 10, 20, 40, 50 }
{ 5, 20, 40, 10 }
{ 10, 20, 40, 10 }
{ 12, 24, 35, 55 }
Sample Output:
bool(true)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
87. Check if First and Last Array Elements are Equal
Write a PHP program to check a given array of integers of length 1 or more and return true if the first element and the last element are equal in the given array.
Sample Input:
{ 10, 20, 40, 50 }
{ 10, 20, 40, 10 }
{ 12, 24, 35, 55 }
Sample Output:
bool(false)
bool(true)
bool(false)
Click me to see the sample solution
88. Check if Two Arrays Share Same Boundary
Write a PHP program to check two given arrays of integers of length 1 or more and return true if they have the same first element or they have the same last element.
Sample Input:
{[10, 20, 40, 50], [10, 20, 40, 50]}
{[10, 20, 40, 10], [10, 20, 40, 5]}
{[12, 24, 35, 55], [1, 20, 40, 5]}
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
89. Sum of Array Elements
Write a PHP program to compute the sum of the elements of an given array of integers.
Sample Input:
{ 10, 20, 30, 40, 50 }
{ 10, 20, -30, -40, 50 }
Sample Output:
150
10
Click me to see the sample solution
90. Rotate Array Elements Left
Write a PHP program to rotate the elements of a given array of integers (length 4 ) in left direction and return the new array.
Sample Input:
{ 10, 20, -30, -40 }
Sample Output:
Rotated array: 20,-30,-40,10
Click me to see the sample solution
91. Reverse Array of Length 5
Write a PHP program to reverse a given array of integers and length 5.
Sample Input:
{ 10, 20, -30, -40, 50 }
Sample Output:
Reverse array: 50,-40,-30,20,10
Click me to see the sample solution
92. Replace All Elements with Maximum of Boundaries
Write a PHP program to find out the maximum element between the first or last element in a given array of integers ( length 4), replace all elements with maximum element.
Sample Input:
{ 10, 20, -30, -40 }
Sample Output:
New array with maximum values: 20,20,20,20
Click me to see the sample solution
93. New Array from Middle Elements of Two Arrays
Write a PHP program to create a new array containing the middle elements from the two given arrays of integers, each length 5.
Sample Input:
{ 10, 20, -30, -40, 30 }, { 10, 20, 30, 40, 30 }
Sample Output:
New array: -30, 30
Click me to see the sample solution
94. New Array of First and Last Elements
Write a PHP program to create a new array taking the first and last elements of a given array of integers and length 1 or more.
Sample Input:
{ 10, 20, -30, -40, 30 }
Sample Output:
New array: 10,30
Click me to see the sample solution
95. Array Contains 15 or 20 Check
Write a PHP program to check if a given array of integers and length 2, contains 15 or 20.
Sample Input:
{ 12, 20 }
{ 14, 15 }
{ 11, 21 }
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
96. Array Does Not Contain 15 or 20 Check
Write a PHP program to check if a given array of integers and length 2, does not contain 15 or 20.
Sample Input:
{ 12, 20 }
{ 14, 15 }
{ 11, 21 }
Sample Output:
bool(false)
bool(false)
bool(true)
Click me to see the sample solution
97. Check for Two Occurrences of 10 or 20
Write a PHP program to check a given array of integers and return true if the array contains 10 or 20 twice. The length of the array will be 0, 1, or 2.
Sample Input:
{ 12, 20 }
{ 20, 20 }
{ 10, 10 }
{ 10 }
Sample Output:
bool(false)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
98. Replace 7 with 1 Following 5 in Array
Write a PHP program to check a given array of integers, length 3 and create a new array. If there is a 5 in the given array immediately followed by a 7 then set 7 to 1.
Sample Input:
{ 1, 5, 7 }
Sample Output:
New array with maximum values: 1,5,1
Click me to see the sample solution
99. Sum of Two Arrays and Largest Sum Array
Write a PHP program to compute the sum of the two given arrays of integers, length 3 and find the array which has the largest sum.
Sample Input:
{ 10, 20, -30 }, { 10, 20, 30 }
Sample Output:
New array with maximum values: 10,20,30
Click me to see the sample solution
100. Array of Middle Two Elements (Even Length)
Write a PHP program to create an array taking two middle elements from a given array of integers of length even.
Sample Input:
{ 1, 5, 7, 9, 11, 13 }
Sample Output:
New array: 7 9
Click me to see the sample solution
101. New Array from Two Arrays
Write a PHP program to create a new array from two give array of integers, each length 3.
Sample Input:
{ 10, 20, 30 }, { 40, 50, 60 }
Sample Output:
New array: 10,20,30,40,50,60
Click me to see the sample solution
102. Swap First and Last Elements in Array
Write a PHP program to create a new array swapping the first and last elements of a given array of integers and length will be least 1.
Sample Input:
{ 1, 5, 7, 9, 11, 13 }
Sample Output:
New array, after swapping first and last elements: 13,5,7,9,11,1
Click me to see the sample solution
103. New Array from Middle Elements
Write a PHP program to create a new array length 3 from a given array (length atleast 3) using the elements from the middle of the array.
Sample Input:
{ 1, 5, 7, 9, 11, 13 }
Sample Output:
New array: 7,9,11
Click me to see the sample solution
104. Largest from First, Last, and Middle
Write a PHP program to find the largest value from first, last, and middle elements of a given array of integers of odd length (atleast 1).
Sample Input:
{1}
{1,2,9}
{1,2,9,3,3}
{1,2,3,4,5,6,7}
{1,2,2,3,7,8,9,10,6,5,4}
Sample Output:
1
9
9
7
8
Click me to see the sample solution
105. New Array from First Two Elements
Write a PHP program to create a new array taking the first two elements from a given array. If the length of the given array is less than 2 then return the give array.
Sample Input:
{ 1, 5, 7, 9, 11, 13 }
Sample Output:
New array: 1,5
Click me to see the sample solution
106. Count Even Numbers in Array
Write a PHP program to count even number of elements in a given array of integers.
Sample Input:
{ 1, 5, 7, 9, 10, 12 }
Sample Output:
Number of even elements: 2
Click me to see the sample solution
107. Difference Between Largest and Smallest
Write a PHP program to compute the difference between the largest and smallest values in a given array of integers and length one or more.
Sample Input:
{ 1, 5, 7, 9, 10, 12 }
Sample Output:
Difference between the largest and smallest values: 11
Click me to see the sample solution
108. Sum of Array Except 17
Write a PHP program to compute the sum of values in a given array of integers except the number 17. Return 0 if the given array has no integer.
Sample Input:
{ 1, 5, 7, 9, 10, 17 }
Sample Output:
Sum of values in the array of integers except the number 17: 32
Click me to see the sample solution
109. Sum Excluding Numbers Starting with 5 Followed by 6
Write a PHP program to compute the sum of the numbers in a given array except those numbers starting with 5 followed by atleast one 6. Return 0 if the given array has no integer.
Sample Input:
{ 1, 5, 7, 9, 10, 17 }
{ 1, 5, 6, 9, 10, 17 }
{ 5, 6, 7, 9, 10, 17, 1 }
{ 11, 9, 10, 17, 5, 6 }
Sample Output:
Sum of the numbers of the said array except those numbers starting with 5 followed by atleast one 6:
49
Sum of the numbers of the said array except those numbers starting with 5 followed by atleast one 6:
37
Sum of the numbers of the said array except those numbers starting with 5 followed by atleast one 6:
44
Sum of the numbers of the said array except those numbers starting with 5 followed by atleast one 6:
47
Click me to see the sample solution
110. Contains 5 Next to 5 Check in Array
Write a PHP program to check if a given array of integers contains 5 next to a 5 somewhere.
Sample Input:
{ 1, 5, 6, 9, 10, 17 }
{ 1, 5, 5, 9, 10, 17 }
{ 1, 5, 5, 9, 10, 17, 5, 5 }
Sample Output:
bool(false)
bool(true)
bool(true)
Click me to see the sample solution
111. Contains Both 5 and 7 in Array
Write a PHP program to check whether a given array of integers contains 5's and 7's.
Sample Input:
{ 1, 5, 6, 9, 10, 17 }
{ 1, 4, 7, 9, 10, 17 }
{ 1, 1, 2, 9, 10, 17}
Sample Output:
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
112. Sum of 5's Equals 15 Check
Write a PHP program to check if the sum of all 5' in the array exactly 15 in a given array of integers.
Sample Input:
{ 1, 5, 6, 9, 10, 17 }
{ 1, 5, 5, 5, 10, 17 }
{ 1, 1, 5, 5, 5, 5}
Sample Output:
bool(false)
bool(true)
bool(false)
Click me to see the sample solution
113. Compare Count of 3's and 5's in Array
Write a PHP program to check if the number of 3's is greater than the number of 5's.
Sample Input:
{ 1, 5, 6, 9, 3, 3 }
{ 1, 5, 5, 5, 10, 17 }
{ 1, 3, 3, 5, 5, 5}
Sample Output:
bool(true)
bool(false)
bool(false)
Click me to see the sample solution
114. Contains 3 or 5 in Array Check
Write a PHP program to check if a given array of integers contains a 3 or a 5.
Sample Input:
{ 5, 5, 5, 5, 5 }
{ 3, 3, 3, 3 }
{ 3, 3, 3, 5, 5, 5}
{ 1, 6, 8, 10}
Sample Output:
bool(true)
bool(true)
bool(true)
bool(false)
Click me to see the sample solution
115. Array Contains No 3 or 5 Check
Write a PHP program to check if a given array of integers contains no 3 or a 5.
Sample Input:
{ 5, 5, 5, 5, 5 }
{ 3, 3, 3, 3 }
{ 3, 3, 3, 5, 5, 5}
{ 1, 6, 8, 10}
Sample Output:
bool(true)
bool(true)
bool(false)
bool(true)
Click me to see the sample solution
116. Contains Adjacent 3's or 5's Check
Write a PHP program to check if an array of integers contains a 3 next to a 3 or a 5 next to a 5 or both.
Sample Input:
{ 5, 5, 5, 5, 5 }
{ 1, 2, 3, 4 }
{ 3, 3, 5, 5, 5, 5}
{ 1, 5, 5, 7, 8, 10}
Sample Output:
bool(true)
bool(false)
bool(true)
bool(true)
Click me to see the sample solution
117. Array Contains Two 5's Next to or Separated by One
Write a PHP program to check a given array of integers and return true if the given array contains two 5's next to each other, or two 5 separated by one element.
Sample Input:
{ 5, 5, 1, 5, 5 }
{ 1, 2, 3, 4 }
{ 3, 3, 5, 5, 5, 5}
{ 1, 5, 5, 7, 8, 10}
Sample Output:
bool(true)
bool(false)
bool(true)
bool(true)
Click me to see the sample solution
118. Array Contains 3 Followed Later by 5
Write a PHP program to check a given array of integers and return true if there is a 3 with a 5 somewhere later in the given array.
Sample Input:
{ 3, 5, 1, 3, 7 }
{ 1, 2, 3, 4 }
{ 3, 3, 5, 5, 5, 5}
{ 2, 5, 5, 7, 8, 10}
Sample Output:
bool(true)
bool(false)
bool(true)
bool(false)
Click me to see the sample solution
119. Check for Two Consecutive Even or Odd Values
Write a PHP program to check a given array of integers and return true if the given array contains either 2 even or 2 odd values all next to each other.
Sample Input:
{ 3, 5, 1, 3, 7 }
{ 1, 2, 3, 4 }
{ 3, 3, 5, 5, 5, 5}
{ 2, 4, 5, 6}
Sample Output:
bool(true)
bool(false)
bool(true)
bool(true)
Click me to see the sample solution
120. Check for Five Occurrences of 5 Without Neighbors
Write a PHP program to check a given array of integers and return true if the value 5 appears 5 times and there are no 5 next to each other.
Sample Input:
{ 3, 5, 1, 5, 3, 5, 7, 5, 1, 5 }
{ 3, 5, 5, 5, 5, 5, 5}
{ 3, 5, 2, 5, 4, 5, 7, 5, 8, 5}
{ 2, 4, 5, 5, 5, 5}
Sample Output:
bool(true)
bool(false)
bool(true)
bool(false)
Click me to see the sample solution
121. Check Every 5 is Paired with Another
Write a PHP program to check a given array of integers and return true if every 5 that appears in the given array is next to another 5.
Sample Input:
{ 3, 5, 5, 3, 7 }
{ 3, 5, 5, 4, 1, 5, 7}
{ 3, 5, 5, 5, 5, 5}
{ 2, 4, 5, 5, 6, 7, 5}
Sample Output:
bool(true)
bool(false)
bool(true)
bool(false)
Click me to see the sample solution
122. Same Number of Elements at Start and End
Write a PHP program to check a given array of integers and return true if the specified number of same elements appears at the start and end of the given array.
Sample Input:
{ 3, 7, 5, 5, 3, 7 }, 2
{ 3, 7, 5, 5, 3, 7 }, 3
{ 3, 7, 5, 5, 3, 7, 5 }, 3
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution
123. Contains Three Increasing Adjacent Numbers
Write a PHP program to check a given array of integers and return true if the array contains three increasing adjacent numbers.
Sample Input:
{ 1, 2, 3, 5, 3, 7 }
{ 3, 7, 5, 5, 3, 7 }
{ 3, 7, 5, 5, 6, 7, 5 }
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution
124. Shift Array Elements Left
Write a PHP program to shift an element in left direction and return a new array.
Sample Input:
{ 10, 20, -30, -40, 50 }
Sample Output:
New array: 20,-30,-40,50,10
Click me to see the sample solution
125. Array Elements Before Value 5
Write a PHP program to create a new array taking the elements before the element value 5 from a given array of integers.
Sample Input:
{ 1, 2, 3, 5, 7 }
Sample Output:
New array: 1,2,3
Click me to see the sample solution
126. Array Elements After Value 5
Write a PHP program to create a new array taking the elements after the element value 5 from a given array of integers.
Sample Input:
{ 1, 2, 3, 5, 7, 9, 11 }
Sample Output:
New array: 7,9,11
Click me to see the sample solution
127. Shift Zeros to Left in Array
Write a PHP program to create a new array from a given array of integers shifting all zeros to left direction.
Sample Input:
{ 1, 2, 0, 3, 5, 7, 0, 9, 11 }
Sample Output:
New array: 0,0,1,3,5,7,2,9,11
Click me to see the sample solution
128. Replace 5 with 0 and Shift Zeros to Right
Write a PHP program to create a new array after replacing all the values 5 with 0 shifting all zeros to right direction.
Sample Input:
{ 1, 2, 0, 3, 5, 7, 0, 9, 11 }
Sample Output:
New array: 1,2,3,7,9,11,0,0,0
Click me to see the sample solution
129. Shift Even Numbers Before Odds in Array
Write a PHP program to create new array from a given array of integers shifting all even numbers before all odd numbers.
Sample Input:
{ 1, 2, 5, 3, 5, 4, 6, 9, 11 }
Sample Output:
New array: 2,4,6,3,5,1,5,9,11
Click me to see the sample solution
130. Check Non-Decreasing Order of Array
Write a PHP program to check if the value of each element is equal or greater than the value of previous element of a given array of integers.
Sample Input:
{ 5, 5, 1, 5, 5 }
{ 1, 2, 3, 4 }
{ 3, 3, 5, 5, 5, 5}
{ 1, 5, 5, 7, 8, 10}
Sample Output:
bool(false)
bool(true)
bool(true)
bool(true)
Click me to see the sample solution
131. Check for Two Adjacent 15's in Array
Write a PHP program to check a given array (length will be atleast 2) of integers and return true if there are two values 15, 15 next to each other.
Sample Input:
{ 5, 5, 1, 15, 15 }
{ 15, 2, 3, 4, 15 }
{ 3, 3, 15, 15, 5, 5}
{ 1, 5, 15, 7, 8, 15}
Sample Output:
bool(true)
bool(false)
bool(true)
bool(false)
Click me to see the sample solution
132. Larger Average between First and Second Halves
Write a PHP program to find the larger average value between the first and the second half of a given array of integers and minimum length is atleast 2. Assume that the second half begins at index (array length)/2.
Sample Input:
{ 1, 2, 3, 4, 6, 8 }
{ 15, 2, 3, 4, 15, 11 }
Sample Output:
6
10
Click me to see the sample solution
133. Count Strings of Given Length in Array
Write a PHP program to count the number of strings with given length in given array of strings.
Sample Input:
{"a", "b", "bb", "c", "ccc" }, 1
Sample Output:
Number of array:
3
Click me to see the sample solution
134. New Array from First n Strings
Write a PHP program to create a new array using the first n strings from a given array of strings. (n>=1 and <=length of the array).
Sample Input:
{"a", "b", "bb", "c", "ccc" }, 3
Sample Output:
a b bb
Click me to see the sample solution
135. Check if Integer Contains Digit 2
Write a PHP program to check a positive integer and return true if it contains a number 2.
Sample Input:
123
13
222
Sample Output:
bool(true)
bool(false)
bool(true)
Click me to see the sample solution
136. New Array from Odd Numbers with Given Length
Write a PHP program to create a new array of given length using the odd numbers from a given array of positive integers.
Sample Input:
{1,2,3,5,7,9,10},3
Sample Output:
New array: 1,3,5
Click me to see the sample solution
PHP Code Editor:
More to Come !
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