J - Следующая буква

#include <bits/stdc++.h>

using namespace std;

int main() {
    char x;
    cin >> x;
    int k = x - 'a';
    k = (k + 1) % 26;
    cout << char(k + 'a');
    return 0;
}

/*
'0' = 48
'1' = 49
'2' = 50
...
'9' = 57

'A' = 65
'B' = 66
'C' = 67
...
'Z' = 90

'a' = 97
'b' = 98
'c' = 99
'd' = 100
...
'z' = 122
*/