C Programming: Check whether a given substring is present in the given string
C String: Exercise-14 with Solution
Write a C program to check whether a substring is present in a string.
Sample Solution:
C Code:
#include <stdio.h>
int main() {
char str[80], search[20]; // Declare character arrays for the main string and the substring to search
int c1 = 0, c2 = 0, i, j, flg; // Declare variables for counting, iteration, and flag for substring check
printf("\n\nCheck whether a given substring is present in the given string :\n"); // Display information about the task
printf("-------------------------------------------------------------------\n");
printf("Input the string : ");
fgets(str, sizeof str, stdin); // Read a string from the standard input (keyboard)
printf("Input the substring to be searched : ");
fgets(search, sizeof search, stdin); // Read the substring to be searched
// Calculate the length of the main string
while (str[c1] != '\0') {
c1++;
}
c1--;
// Calculate the length of the substring
while (search[c2] != '\0') {
c2++;
}
c2--;
// Check if the substring exists in the main string
for (i = 0; i <= c1 - c2; i++) {
for (j = i; j < i + c2; j++) {
flg = 1; // Initialize the flag for matching substring
if (str[j] != search[j - i]) {
flg = 0; // Set the flag to zero if characters don't match
break;
}
}
if (flg == 1) {
break; // Break the loop if substring is found
}
}
if (flg == 1) {
printf("The substring exists in the string.\n\n"); // Display message if the substring is found
} else {
printf("The substring does not exist in the string.\n\n"); // Display message if the substring is not found
return 0; // Return 0 to indicate successful execution of the program
}
}
Sample Output:
Check whether a given substring is present in the given string : ------------------------------------------------------------------- Input the string : This is a test string. Input the substring to be search : search The substring is not exists in the string.
Flowchart :
C Programming Code Editor:
Improve this sample solution and post your code through Disqus.
Previous: Write a program in C to extract a substring from a given string.
Next: Write a program in C to read a sentence and replace lowercase characters by uppercase and vice-versa.
What is the difficulty level of this exercise?
Test your Programming skills with w3resource's quiz.
It will be nice if you may share this link in any developer community or anywhere else, from where other developers may find this content. Thanks.
https://w3resource.com/c-programming-exercises/string/c-string-exercise-14.php
- Weekly Trends and Language Statistics
- Weekly Trends and Language Statistics