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>
#include<stdlib.h>
#include <string.h>
 
int main(){
	int n,k;
	scanf("%d",&n);
	scanf("%d",&k);
	k=k-1;
	char s[1000];
	scanf("%s",s);

		if(s[k]=='A'){
			s[k]='a';}
			
		else if(s[k]=='B'){
			s[k]='b';}
			
		else  if(s[k]=='C'){
		s[k]='c';}
 
printf("%s",s);
    return 0;}