from collections import Counter

N = int(input())
A = list(map(int,input().split()))
B = list(map(int,input().split()))

c1 = Counter(A)
c2 = Counter(B)

ans = 0
for k,v in c1.items():
	if c2[k] == 0 or c2[k] != v:
		ans = k 
print(ans)