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 JavaScript (judge verdict: Wrong Answer)

var input = '';
var readable = process.stdin;
readable.resume();
readable.setEncoding( 'utf-8' );
readable.on( 'data', function( chunk ) {
  input += chunk;
});

readable.on( 'end', function() {
  var size = 'z'.charCodeAt(0)-'a'.charCodeAt(0);
  var cnt = [];
  for( var i=0; i<size; i++ ) { cnt.push( 0 ); }
  
  for( var i=0; i<input.length; i++ ) {
    var az = input.toLowerCase().charCodeAt( i )-'a'.charCodeAt(0);
    if( 0 <= az ) {
      cnt[ az ]++;
    }
  }
  for( var i=0; i<size; i++ ) {
    console.log( String.fromCharCode( 'a'.charCodeAt(0)+i ) + " : "+cnt[i] );
  }
});