Problem:
Score : 200 points

Problem Statement

Given are strings S and T. Consider changing S to T by repeating the operation below. Find the minimum number of operations required to do so.

Operation: Choose one character of S and replace it with a different character.

Constraints

S and T have lengths between 1 and 2\times 10^5 (inclusive).

S and T consists of lowercase English letters.

S and T have equal lengths.

Input

Input is given from Standard Input in the following format:

S
T

Output

Print the answer.

Sample Input 1

cupofcoffee
cupofhottea

Sample Output 1

4

We can achieve the objective in four operations, such as the following:

First, replace the sixth character c with h.

Second, replace the eighth character f with t.

Third, replace the ninth character f with t.

Fourth, replace the eleventh character e with a.

Sample Input 2

abcde
bcdea

Sample Output 2

5

Sample Input 3

apple
apple

Sample Output 3

0

No operations may be needed to achieve the objective.

Solution in JavaScript (Node.js 12.16.1) (judge verdict: Accepted)

const main = async () => {
  'use strict'
  const input = require('fs').readFileSync('/dev/stdin', 'UTF-8').trim()
  
  let setting = input.split('\n')
  
  const str = setting[0].split('')
  const sample = setting[1].split('')

  let count = 0

  for (let i = 0; i < str.length; i++) {
    if (str[i] !== sample[i]) {
      count++
    }
  }

  console.log(count)
}

main()