You planned a trip using trains and buses. The train fare will be A yen (the currency of Japan) if you buy ordinary tickets along the way, and B yen if you buy an unlimited ticket. Similarly, the bus fare will be C yen if you buy ordinary tickets along the way, and D yen if you buy an unlimited ticket.  Find the minimum total fare when the optimal choices are made for trains and buses.
a=input()
b=input()
c=input()
d=input()
print(min(a,b)+min(c,d))
a=int(input())
b=int(input())
c=int(input())
d=int(input())
print(min(a,b)+min(c,d))