import sys
rr = lambda: sys.stdin.readline().rstrip()
rm = lambda: map(int, sys.stdin.buffer.readline().split())
a, b = rm()
s = rr()
print(s[:b-1] + s[b-1].lower() + s[b:]) import sys sys rr = lambda: sys.stdin.readline().rstrip() rr lambda: sys.stdin.readline().rstrip() sys.stdin.readline().rstrip() sys.stdin.readline().rstrip sys.stdin.readline() sys.stdin.readline sys.stdin sys stdin readline rstrip rm = lambda: map(int, sys.stdin.buffer.readline().split()) rm lambda: map(int, sys.stdin.buffer.readline().split()) map(int, sys.stdin.buffer.readline().split()) map int sys.stdin.buffer.readline().split() sys.stdin.buffer.readline().split sys.stdin.buffer.readline() sys.stdin.buffer.readline sys.stdin.buffer sys.stdin sys stdin buffer readline split a, b = rm() a rm() rm b s = rr() s rr() rr print(s[:b-1] + s[b-1].lower() + s[b:]) print s[:b-1] + s[b-1].lower() + s[b:] s[:b-1] + s[b-1].lower() s[:b-1] s :b-1 b-1 b 1 s[b-1].lower() [b-1].lower [b-1] s b-1 b 1 lower s[b:] s b: b rr = lambda: sys.stdin.readline().rstrip() lambda: sys.stdin.readline().rstrip() rr rm = lambda: map(int, sys.stdin.buffer.readline().split()) lambda: map(int, sys.stdin.buffer.readline().split()) rm b = rm() rm() b a, b = rm() rm() a s = rr() rr() s
import sys
rr = lambda: sys.stdin.readline().rstrip()
rm = lambda: map(int, sys.stdin.buffer.readline().split())
a, b = rm()
s = rr()
print(s[:b-1] + s[b-1].lower() + s[b:])
