1.1 KB | 1109 chars
"""
[1622: 공통 순열](https://www.acmicpc.net/problem/1622)
Tier: Silver 4
Category: sorting, string
"""
import sys
from math import sqrt, pi, sin, factorial, ceil, floor
from datetime import datetime, timedelta
SYS_INPUT = False
RECURSION_LIMIT = 10 ** 7
SET_RECURSION = False
BLANK = " "
if SET_RECURSION:
sys.setrecursionlimit(RECURSION_LIMIT)
inp = lambda : sys.stdin.readline().rstrip() if SYS_INPUT else input()
mii = lambda : [*map(int,inp().split())]
mfi = lambda : [*map(float,inp().split())]
ii = lambda : int(inp())
fi = lambda : float(inp())
isplit = lambda : inp().split()
p = print
def gcd(a, b): return gcd(b, a % b) if b > 0 else a
def lcm(a, b): return a * b // gcd(a, b)
def solve():
while 1:
try:
a = inp()
b = inp()
except:
break
a = sorted(a)
b = sorted(b)
i = j = 0
while i < len(a) and j < len(b):
if a[i] < b[j]:
i += 1
elif a[i] > b[j]:
j += 1
else:
p(a[i], end="")
i += 1
j += 1
p()
if __name__ == "__main__":
tc = 1
for t in range(1, tc+1):
ret = solve()