Program to find out if the strings supplied differ by a character in the same position in Python

Suppose, we are provided an array that contains several strings that are of the same length. We have to find out if any two of the supplied strings differ by a single character at the same position. If this difference is present, we return true or else we return false.

So, if the input is like dict = ['pqrs', 'prqs', 'paqs'], then the output will be True. The output produced is True because the strings listed in the input all differ in index 1. So, if any two pairs are taken, there is a difference in the same position.

To solve this, we will follow these steps −

• seens := a new set

• for each word in dict, do

  • for each index i and character c in word, do

    • masked_word := word[from index 0 to i] + '.' + word[from index i+1 to end of string]

    • if masked_word is present in seens, then

      • return True

    • otherwise,

      • add(masked_word) to seens

• return False

Example (Python)

Let us see the following implementation to get better understanding −

 Live Demo

def solve(dict):
   seens = set()
   for word in dict:
      for i, c in enumerate(word):
         masked_word = word[:i] + '.' + word[i+1:]
         if masked_word in seens:
            return True
         else:
            seens.add(masked_word)
   return False

print(solve(['pqrs', 'prqs', 'paqs']))

Input

['pqrs', 'prqs', 'paqs']

Output

True