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 Ruby (2.3.3) (judge verdict: Runtime Error)

N, K, M = gets.chomp.split(" ").map(&:to_i)
A= gets.chomp.split(" ").map(&:to_i)

if M * N - A.inject(:+) > K
    puts "-1"
elsif (M * N - A.inject(:+) > 0) && (M * N - A.inject(:+) < K)
    puts "#{M * N - A.inject(:+)}"
else 
    puts 0
end