for tcase in range(int(input())):
    n,m=map(int,input().split())
    a,b=set(),set()
    for i in range(n):
        s,e=map(int,input().split())
        a=a|set(range(s,e+1))

    for i in range(m):
        s,e=map(int,input().split())
        b=b|set(range(s,e+1))

    print(len(a&b))