N, K = (int(x) for x in input().split())
S = input()

S = S[:K-1] +S[K-1].lower() +S[K:]
print(S) int(x) for x in input().split() for x in input().split() x input().split() ().split () input split for x in input().split() int(x) int x N, K = (int(x) for x in input().split()) N (int(x) for x in input().split()) K S = input() S input() input S = S[:K-1] +S[K-1].lower() +S[K:] S S[:K-1] +S[K-1].lower() +S[K:] S[:K-1] +S[K-1].lower() S[:K-1] S :K-1 K-1 K 1 S[K-1].lower() [K-1].lower [K-1] S K-1 K 1 lower S[K:] S K: K print(S) print S S = input() input() S S = S[:K-1] +S[K-1].lower() +S[K:] S[:K-1] +S[K-1].lower() +S[K:] S K = (int(x) for x in input().split()) (int(x) for x in input().split()) K N, K = (int(x) for x in input().split()) (int(x) for x in input().split()) N
N, K = (int(x) for x in input().split())
S = input()

S = S[:K-1] +S[K-1].lower() +S[K:]
print(S)
