Python: Count number of substrings with same first and last characters of a given string

Last update on March 21 2025 12:53:51 (UTC/GMT +8 hours)

Substrings with same first and last char.

Write a Python program to count the number of substrings with the same first and last characters in a given string.

Visual Presentation:

Sample Solution:

Python Code:

# Function to count substrings with equal ends
def no_of_substring_with_equalEnds(str1):

  result = 0;
  
  # Get string length
  n = len(str1);

  # Generate all substrings
  for i in range(n):
    for j in range(i, n):
      
      # Check if ends are equal
      if (str1[i] == str1[j]):
        result = result + 1

  return result

# Get input string  
str1 = input("Input a string: ")

# Print result
print(no_of_substring_with_equalEnds(str1))

Sample Output:

Input a string:  abc
3

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Python program to count the number of substrings in a string where the first and last characters are identical.
• Write a Python program to generate all substrings that begin and end with the same character and return their count.
• Write a Python program to use nested loops to check each substring for matching first and last characters and tally the total.
• Write a Python program to implement this substring check using recursion and compare the results with an iterative approach.

Python Code Editor:

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