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 <string.h>
     
    int main()
    {
      int i,j,k,n,m;
      
      scanf("%d %d",&n,&m);
      
      char a[n];
      
      scanf("%s",a);
      
      a[m-1]=a[m-1]+32;
      printf("%s",a);
      
      return 0;
    }