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 JAVA (judge verdict: Accepted)

import java.util.Arrays;
import java.util.Scanner;

public class Main {
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    int [] Alp = new int[26];
    int [] count = new int[26];
    Arrays.fill(count, 0);
    int k;
    Alp[0] = 'a';
    for(int i=1;i<26;i++){
      Alp[i] = Alp[0] + i;
    }
    while(sc.hasNext()){
      String sen = sc.next();
      sen = sen.toLowerCase();
      for(int i=0;i<sen.length();i++){
        k = sen.charAt(i);
        for(int j=0;j<26;j++){
          if(Alp[j] == k){
            count[j]++;
          }
        }
      }
    }
    sc.close();
    for(int i=0;i<26;i++){
      System.out.println((char)Alp[i] + " : " + count[i]);
    }
  }
}