n, k = map(int, input().split())
s = input().rstrip()

k -= 1
print(s[:k] + s[k].lower() + s[k+1:]) n, k = map(int, input().split()) n map(int, input().split()) map int input().split() ().split () input split k s = input().rstrip() s input().rstrip() ().rstrip () input rstrip k -= 1 k 1 print(s[:k] + s[k].lower() + s[k+1:]) print s[:k] + s[k].lower() + s[k+1:] s[:k] + s[k].lower() s[:k] s :k k s[k].lower() [k].lower [k] s k lower s[k+1:] s k+1: k+1 k 1 k = map(int, input().split()) map(int, input().split()) k n, k = map(int, input().split()) map(int, input().split()) n k -= 1 1 k s = input().rstrip() input().rstrip() s
n, k = map(int, input().split())
s = input().rstrip()

k -= 1
print(s[:k] + s[k].lower() + s[k+1:])