N,K=map(int,input().split())
S=list(map(str,input()))

S[K-1]=S[K-1].lower()

for i in range(N):
    print(S[i],end="") N,K=map(int,input().split()) N map(int,input().split()) map int input().split() ().split () input split K S=list(map(str,input())) S list(map(str,input())) list map(str,input()) map str input() input S[K-1]=S[K-1].lower() S[K-1] S K-1 K 1 S[K-1].lower() [K-1].lower [K-1] S K-1 K 1 lower for i in range(N):
    print(S[i],end="") i range(N) range N print(S[i],end="") print S[i] S i end="" end "" N,K=map(int,input().split()) map(int,input().split()) N K=map(int,input().split()) map(int,input().split()) K S=list(map(str,input())) list(map(str,input())) S
N,K=map(int,input().split())
S=list(map(str,input()))

S[K-1]=S[K-1].lower()

for i in range(N):
    print(S[i],end="")