n,k=map(int,input().split())
a = input()
 
a = list(a)
a[k - 1] = a[k-1].lower()
a = "".join(a)
print(a) n,k=map(int,input().split()) n map(int,input().split()) map int input().split() ().split () input split k a = input() a input() input a = list(a) a list(a) list a a[k - 1] = a[k-1].lower() a[k - 1] a k - 1 k 1 a[k-1].lower() [k-1].lower [k-1] a k-1 k 1 lower a = "".join(a) a "".join(a) "".join "" join a print(a) print a n,k=map(int,input().split()) map(int,input().split()) n a = list(a) list(a) a a = input() input() a k=map(int,input().split()) map(int,input().split()) k a = "".join(a) "".join(a) a
n,k=map(int,input().split())
a = input()
 
a = list(a)
a[k - 1] = a[k-1].lower()
a = "".join(a)
print(a)