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 sc = new Scanner(System.in);

        String S = sc.next();
        int format = Integer.parseInt(S);
        int left = format / 100;
        int right = format % 100;

        if (left >= 1 && left <= 12) {
            if (right >= 1 && right <= 12) {
                System.out.println("AMBIGUOS");
            } else {
                System.out.println("MMYY");
            }
        } else {
            if (right >= 1 && right <= 12) {
                System.out.println("YYMM");
            } else {
                System.out.println("NA");
            }
        }

    }
}