for tcase in range(int(input())):
    n,m = map(int,input().split())
    a,b = [0 for i in range(24)],[0 for i in range(24)]
    for i in range (n):
        s,e = map(int, input().split())
        a[s:e+1] = [1]*(e-s+1)
    for i in range (m):
        s,e = map(int, input().split())
        b[s:e+1] = [1]*(e-s+1)

    total = 0
    for i in range (24):
        if a[i] ==1 and b[i] == 1:
            total = total + 1
    print(total)