_,s,k=open(0);print((''.join(t*(t==s[int(k)-1])or'*'for t in s[:-1])))
import re;_,s,k=open(0);print((re.sub('[^%s]'%s[int(k)-1],'*',s[:-1])))
_, s, k = open(0)
print(("".join(t * (t == s[int(k) - 1]) or "*" for t in s[:-1])))

import re

_, s, k = open(0)
print((re.sub("[^%s]" % s[int(k) - 1], "*", s[:-1])))

+import re + -print(("".join(t * (t == s[int(k) - 1]) or "*" for t in s[:-1]))) +print((re.sub("[^%s]" % s[int(k) - 1], "*", s[:-1])))