Problem:
Score : 100 points

Problem Statement

Given is a lowercase English letter C that is not z. Print the letter that follows C in alphabetical order.

Constraints

C is a lowercase English letter that is not z.

Input

Input is given from Standard Input in the following format:

C

Output

Print the letter that follows C in alphabetical order.

Sample Input 1

a

Sample Output 1

b

a is followed by b.

Sample Input 2

y

Sample Output 2

z

y is followed by z.

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

#pragma gcc optimize("Ofast")
#include <bits/stdc++.h>

using namespace std;
using ll = long long;

#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define REP(i, n) for (int i = 0; i < (n); ++i)
#define SORT(V) sort((V).begin(),(V).end())
#define pb push_back
#define endl '\n'
#define int long long

const int MOD = 1000000007;
const int INF = 1061109567;
const double EPS = 1e-10;
const double PI  = acos(-1.0);

// 変数定義
char s;
//

signed main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cin >> s;
  int c = 0;
  for(char i = s; i < 'z'; i++) {
    s = i;
    if(c==1) break;
    c++;
  }
  cout << s << endl;
}