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: Wrong Answer)

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);

		int N = scan.nextInt();
		int K = scan.nextInt();

		String S = scan.next();
		char[] list = new char[N] ;

		for (int i = 0; i < N; i++) {
			list[i] = S.charAt(i) ;

			if (i == K - 1) {
				if (list[i] == 'A') {
					list[i] = 'a' ;
				}
				else if (list[i] == 'B') {
					list[i] = 'b' ;
				}
				else if (list[i] == 'C') {
					list[i] = 'c' ;
				}
			}
		}
		for (int i = 0; i < N; i++) {
			System.out.println(list[i]);
		}
	}
}