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: Runtime Error)

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

namespace CsProgramSpace
{
    class Program
    {
        static void Main(string[] args)
        {
            string inp="";
            string temp;
            while (true)
            {
                temp = Console.ReadLine();
                inp += temp;
                if (temp.IndexOf(".") > -1)
                    break;
            }
            char[] table = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z' };
            int[] ctable = new int[26];
            for (int i = 0; i < inp.Length; i++)
            {
                for (int j = 0; j < 26; j++)
                {
                    char[] c = inp.ToCharArray();
                    if (char.ToLower(c[i]) == table[j]) ctable[j]++;
                }
            }
            for (int i = 0; i < 26; i++)
            {
                Console.WriteLine($"{table[i]} : {ctable[i]}");
            }
        }
    }
}