p03041 AtCoder Beginner Contest 126 - Changing a Character
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.

Examples

Input

3 1
ABC


Output

aBC


Input

4 3
CABA


Output

CAbA
```python
a, b = map(int, input().split(' '))
c = input()
print(c[:b-1]+c[b-1:b].lower()+c[b:])
```