HackerEarth ( Problem A ) Pikachu and the Game of Strings problem solution

In this HackerEarth (Problem A) Pikachu and the Game of Strings problem solution, Pikachu has recently learnt a new move s. He knows he can work hard and convert it into a stronger move t. Both the moves s and t contain the same number of letters.

In a single day, Pikachu can increase any letter of move s by one, that is, in a single day, he can convert letter A to B, C to D, M to N and so on. He can also convert letter Z to letter A. 

Pikachu just realized he also has a hidden ability. It can help him increase any letter of move s by 13, that is, in a single day, he can convert letter A to letter N, B into O, M into Z, O into B and so on.  

Now Pikachu wants to know the minimum number of days in which he can convert the move s into move t ?

#include <bits/stdc++.h>

using namespace std;

int main(){
    int n;
    cin>>n;
    string s,t;
    cin>>s>>t;
    int ans=0;
    for(int i=0;i<n;i++){
        ans+=min((t[i]-s[i]+26)%26,1+(t[i]-(s[i]+13)+52)%26);
    }
    cout<<ans<<endl;
}