# Enter your code here. Read input from STDIN. Print output to STDOUT
input1=map(int,raw_input().strip().split(' '))
input2=map(int,raw_input().strip().split(' '))
input3=map(int,raw_input().strip().split(' '))

list=[0,0,0,0,0,0,0,0,0]
for each in input1:
    list[each-1]+=1
for each in input2:
    list[each-1]+=1
for each in input3:
    list[each-1]+=1
    
val1=list.index(0)
val2=list.index(2)
print abs(val1-val2)