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.*;
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String line = sc.nextLine();
        String[] line1 = line.split(" ");
        int a = Integer.parseInt(line1[0]);
        int b = Integer.parseInt(line1[1]);
        String line2 = sc.nextLine();
        char[] line3 = line2.toCharArray();
        
        char c = line2.charAt(b - 1);
        c += 32;
        line3[b - 1] = c;
        for(char c1 : line3) {
            System.out.print(c1);
        }
    }
}