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: Wrong Answer)

using System;
using System.Collections.Generic;
using System.Linq;
public class Hello{
    public static void Main(){
        var alph = "abcdefghijklmnopqrstuvwxyz";
        var list = new List<int>();
        while(true){
            var s = Console.ReadLine();
            if(s == null) break;
            
            s = s.ToLower();
            for(var i = 0;i < alph.Length;i++){
                var count = s.Count(x => x == alph[i]);
                list.Add(count);
            }
            
        }
        for(var i = 0;i < 26;i++){
            Console.WriteLine($"{alph[i]} : {list[i]}");
        }
    }
}