while True:
try:
num_1 = int(input())
a = list(map(int,input().split()))
num_2 = int(input())
b = list(map(int,input().split()))
a = set(a) #变为集合(自动去重)
b = set(b) #变为集合
c = a | b #求并集,交集为&
c = list(c)
c.sort() #排序,默认从小到大
for i in range(len(c)): #按要求输出
c[i] = str(c[i])
print(''.join(c))
except:
break