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: Wrong Answer)

#include<stdio.h>
int main(void){
  int N,k;
  char s[50];
  scanf("%d %d\n%c",&N,&k,s);
  switch(s[k-1]){
    case 'A':
      s[k-1]='a';
      break;
    case 'B':
      s[k-1]='b';
      break;
    case 'C':
      s[k-1]='b';
      break;
  }
  printf("%s",s);
  return 0;
}