Simple Fun #265: The Janitor And His Mop

Simple Fun #265: The Janitor And His MopCodewars

Approach

Find pattern

• it must iterate 26 times (all charaters)from a-z

• count difference last to begin

solve the problem

1. make new 26 size array and fill with 0

2. repeat all array and

   1. make character use index

   2. check fist index and last index

   3. if index exists return lastIndex - firstIndex +1

   4. if the index does not exist return 0

Solutions

JavaScript

// simple-fun-265-the-janitor-and-his-mop
// Simple Fun #265: The Janitor And His Mop
// https://www.codewars.com/kata/59128363e5bc24091a00006f

const theJanitor = (word) => new Array(26).fill(0).map((v, i) => {
  let targetCharacter = String.fromCharCode(97 + i);
  let firstIndex = word.indexOf(targetCharacter);
  let lastIndex = word.lastIndexOf(targetCharacter);
  
  return firstIndex === -1 ? 0 : lastIndex - firstIndex + 1;
});