Problem:
Score : 100 points

Problem Statement

You are given a string S of length N consisting of A, B and C, and an integer K which is between 1 and N (inclusive).
Print the string S after lowercasing the K-th character in it.

Constraints

1 ≤ N ≤ 50

1 ≤ K ≤ N

S is a string of length N consisting of A, B and C.

Input

Input is given from Standard Input in the following format:

N K
S

Output

Print the string S after lowercasing the K-th character in it.

Sample Input 1

3 1
ABC

Sample Output 1

aBC

Sample Input 2

4 3
CABA

Sample Output 2

CAbA

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.Scanner;

public class Main {
	String [] words = new String[100];
	private Scanner kb;
	public void process() {
		kb = new Scanner(System.in);
		int N = kb.nextInt();
		int K = kb.nextInt();
		String S = kb.next();
		
		for(int i=0; i<N; i++) {
			words[i] = S.substring(i,i+1);
		}
		words[K-1] = words[K-1].toLowerCase();
		for(int i=0; i<N; i++) {
			System.out.print(words[i]);
		}
	}

	public static void main(String [] args) {
		Main app = new Main();
		app.process();
	}
}