No Idea!

  • + 99 comments

    List comprehensions can do this easily, esp when you leverage that True == 1 and False == 0:

    n, m = raw_input().split()
    
    sc_ar = raw_input().split()
    
    A = set(raw_input().split())
    B = set(raw_input().split())
    print sum([(i in A) - (i in B) for i in sc_ar])