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)

c = gets.chomp.split(' ').map(&:to_i)
# array でa~zの配列をつくる
array = ("a".."z")to_a
# find で条件に一致した要素を取り出す
# オブジェクト.find{ |要素| ブロック処理}

num = array.find_num(c)

puts array[num + 1]