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: Runtime Error)

import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		int N = sc.nextInt();
		int K = sc.nextInt();
		String S [] = new String [N]; 
		for(int x=0; x<N; x++) {
		    S[x]= sc.next();
		}
		    
		if(N>=1 && N<=50 && K>=1 && K<=N) {
			for(int i=0; i<N; i++) {
				if(i==K-1) {
					S[i] = S[i].toLowerCase();
				}		    
				System.out.print(S[i]);
			}
		}
	}
}