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

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