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 Python (3.4.3) (judge verdict: Runtime Error)

n, k, m = map(int, input().split())
a = map(int, input().split())

if m * n - sum(a) <= 0:
    print(0)

elif 0 < m * n - sum(a) <= k:
    print(m * n - sum(a))
    
else:
    print('-1')