Problem:
Counting Characters

Write a program which counts and reports the number of each alphabetical letter. Ignore the case of characters.

Input

A sentence in English is given in several lines.

Output

Prints the number of alphabetical letters in the following format:

a : The number of 'a'
b : The number of 'b'
c : The number of 'c'
.
.
z : The number of 'z'

Constraints

The number of characters in the sentence < 1200

Sample Input

This is a pen.

Sample Output

a : 1
b : 0
c : 0
d : 0
e : 1
f : 0
g : 0
h : 1
i : 2
j : 0
k : 0
l : 0
m : 0
n : 1
o : 0
p : 1
q : 0
r : 0
s : 2
t : 1
u : 0
v : 0
w : 0
x : 0
y : 0
z : 0

Solution in C# (judge verdict: Accepted)

using System;

class Sample31
{
    static void Main()
    {
        int[] ret = new int[500];
            
        while (true)
        {
             string s = Console.ReadLine();
                
            //終了処理
            if (s == null) 
            {
                break;
            }
                
            s = s.ToLower();
            for (int i = 0; i < s.Length; i++)
            {
                ret[s[i]]++;
            }
        }
            
        //出力
        for (int i = 'a'; i <= 'z'; i++)
        {
      
            Console.WriteLine((char)i + " : " + ret[i]);
        }
    }
}