Single Mutation

We'll determine how to tell if two different strings are similar or extremely different. We'll also cover the idea of the double-condition loop, another tool to add to our repertoire.

Single Mutation


There are 3 types of possible string mutations: character insertion, character deletion, or character substitution. Write a function that accepts 2 strings and returns true if the strings are the same except for 0 or 1 mutations. Return false otherwise.

Inputs: String, String

Output: Boolean


  • Single Deletion:

    • 'abcd', 'abc'
    • 'abcd', 'acd'
  • Single Insertion:

    • 'abcd', 'abcde'
    • 'abcd', 'abXcd'
  • Single Substitution:

    • 'abcd', 'abXd'
    • 'abcd', 'Xbcd'

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