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 C (GCC 5.4.1) (judge verdict: Accepted)

#include <stdio.h>

int main(void) {

	int N;
	int K;
	char S[112];

	scanf("%d %d", &N, &K);
    scanf("%s",S);

		if (S[K - 1] == 'A') {
          S[K - 1] = 'a';
		}
		else if (S[K - 1] == 'B') {
          S[K - 1] = 'b';
		}
		else if (S[K - 1] == 'C') {
          S[K - 1] = 'c';
		}
  
  printf("%s",S);

	return 0;
}