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.Scanner;
import java.util.HashMap;
public class Main {
  public static void main(String[] args) {
    Scanner s = new Scanner(System.in);
    StringBuilder lines = new StringBuilder();
    String line;
    while (s.hasNextLine()) {
        line = s.nextLine();
        if (line.isEmpty())
            break;
        lines.append(line);
    }
    s.close();
    String sent = lines.toString();
    sent = sent.toLowerCase();
    HashMap<Character, Integer> map = new HashMap<Character, Integer>();
    for (char i = 'a'; i <= 'z'; i++) {
      map.put(i, 0);
    }
    for (int i = 0; i < sent.length(); i++) {
      Character c = sent.charAt(i);
      if (Character.isLetter(c)) {
        int prev = map.get(c);
        map.put(c, prev+1);
      }
    }
    for (char i = 'a'; i <= 'z'; i++) {
      int count = map.get(i);
      System.out.println(i + " : " + count);
    }
  }
}