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 s;
  scanf("%d",&s);
  int t = s % 100;
  int u = s - t;
  if(t>=1&&t<=12){
    if(u>=1&&u<=12){
      printf("AMBIGUOUS");
    }
    if(u==0||u>=13){
      printf("YYMM");
    }
  }
  else{
    if(u>=1&&u<=12){
      printf("MMYY");
    }
    if(u==0||u>=13){
      printf("NA");
    }
  }
}