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 C++ (GCC 9.2.1) (judge verdict: Accepted)

#include<bits/stdc++.h>

#define all(n) n.begin(),n.end()
#define ll long long

#define pb push_back
#define eb emplace_back
#define endl "\n"
#define pll pair<ll,ll>

#define ff first
#define ss second

using namespace std;
const ll maxn=1e6+2;
const ll maxx=1e16;
const ll mod=998244353;
const ll mod1=998244353;

vector<ll>  ans[maxn];
pll a[maxn];
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    if (fopen("TEAMS.INP","r"))
    {
        freopen("TEAMS.INP", "r", stdin);
        freopen("TEAMS.OUT", "w", stdout);
    }
   string s;
    string t;
     cin>>s>>t;
      ll ans=0;
      for (int i=0;i<s.length();i++)
      {
          if (s[i]!=t[i]) ans++;
      }
      cout <<ans;



}