646 B | 646 chars
import sys
from math import sqrt, pi, sin, factorial
inp = lambda : sys.stdin.readline()[:-1].strip()
mii = lambda x = " " : [*map(int,inp().split(x))]
mfi = lambda x = " " : [*map(float,inp().split(x))]
ii = lambda : int(inp())
fi = lambda : float(inp())
p = print
def solve():
key = input()
s = input()
ans = ""
for i in s:
if "A" <= i <= "Z":
k = ord(i) - 65
ans += key[k].upper()
elif "a" <= i <= "z":
k = ord(i) - 97
ans += key[k]
else:
ans += i
return ans
if __name__ == "__main__":
tc = 1
for t in range(1, tc+1):
ret = solve()
if ret == None:
break
p(ret)