Problem:
Score : 100 points

Problem Statement

Given is a string S representing the day of the week today.

S is SUN, MON, TUE, WED, THU, FRI, or SAT, for Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, and Saturday, respectively.

After how many days is the next Sunday (tomorrow or later)?

Constraints

S is SUN, MON, TUE, WED, THU, FRI, or SAT.

Input

Input is given from Standard Input in the following format:

S

Output

Print the number of days before the next Sunday.

Sample Input 1

SAT

Sample Output 1

1

It is Saturday today, and tomorrow will be Sunday.

Sample Input 2

SUN

Sample Output 2

7

It is Sunday today, and seven days later, it will be Sunday again.

Solution in C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>
using namespace std;
int main(void){
    int cnt,n;
    int i;
    string s;
    cin>>s;
    n=s.size();
    cnt=0;
   // cout<<n/2<<endl;
    for(i=0;i<n/2;i++){
     //   cout<<s[i]<<" "<<s[n-i-1]<<endl;
        if(s[i]!=s[n-i-1])    cnt++;
    }
    cout<<cnt<<endl;
}