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;

class Main{
	public static void main (String[] args) {
		Scanner stdIn = new Scanner(System.in);
		int n = stdIn.nextInt();
		int k = stdIn.nextInt();
		String s = stdIn.nextLine();
	    char[] a = new char[n];
	    for(int i = 0;i < n;i++)
	    	a[i] = s.charAt(i);
	    if(a[k] == 'A')
	    	a[k] = 'a';
	    else if(a[k] == 'B')
	    	a[k] = 'b';
	    else
	    	a[k] = 'c';
	    for(int i = 0;i < n;i++)
	    	System.out.print(a[i]);
	}
}