N = int(input())
A = input().split()
B = input().split()
da = dict()
db = dict()
for a in A:
    if a in da:
        da[a] += 1
    else:
        da[a] = 1
for b in B:
    if b in db:
        db[b] += 1
    else:
        db[b] = 1
import sys
for k in da:
    if k not in db:
        print(k)
        exit()
    if da[k] > db[k]:
        print(k)
        exit()