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;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;

namespace _20170409_AOJ
{
    class Program
    {
        static void Main(string[] args)
        {
            int[] letters = new int[26];
            for (;;)
            {
                string line = Console.ReadLine();
                if (line == null || line == "")
                {
                    break;
                }

                char[] cArr = line.ToCharArray();
                foreach (var v in cArr)
                {
                    int lc = v - 'a';
                    int uc = v - 'A';
                    if (lc >= 0 && lc < 26)
                    {
                        letters[lc]++;
                    }
                    else if (uc >= 0 && uc < 26)
                    {
                        letters[uc]++;
                    }
                }
            }

            for (int i = 0; i < 26; i++)
            {
                Console.WriteLine("{0} : {1}", (char)('a' + i), letters[i]);
            }

            Console.ReadLine();
        }
    }
}