#include<bits/stdc++.h>
using namespace std;
int main(){
	char n;
	cin>>n;
	if(n=='z') cout<<"a";
	else if(n=='Z') cout<<"A";
	else cout<<char(n+1);
}
/**************************************************************
	Problem: 1969
	User: wangyiyang
	Language: C++
	Result: Accepted
	Time:36 ms
	Memory:2072 kb
****************************************************************/