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.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Test
{
    class ForStudy
    {
        public static void Main(string[] args)
        {
            var num = new int[26];
            string str;
            while ((str = Console.ReadLine())!=null)
            {
                if (str == "")
                {
                    break;
                }
                foreach (char c in str)
                {
                    if (char.IsUpper(c))
                    {
                        try
                        {
                            num[char.ToLower(c) - 'a']++;
                        }
                        catch
                        {

                        }

                    }
                    else
                    {
                        try
                        {
                            num[c - 'a']++;
                        }
                        catch
                        {

                        }
                    }
                }
            }

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