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>

int main(void){
    int num, att, i;
    char *message;

    scanf("%d %d", &num, &att);
    message=(char*)malloc(sizeof(char)*(num+1));
    (void)getchar();
    for(i=0;i<num;i++){
        scanf("%c", &message[i]);
    }

    message[att-1]+=32;
    printf("%s\n", message);
    return 0;
}