tcase=int(raw_input())
for case in range(tcase):
    time1=[]
    time2=[]
    for i in range(24):
        time1.append(0)
        time2.append(0)
    n1,n2=map(int,raw_input().strip().split())
    for i in range(n1):
        a,b=map(int,raw_input().strip().split())
        for j in range(a,b+1):
            time1[j]=1
    for i in range(n2):
        a,b=map(int,raw_input().strip().split())
        for j in range(a,b+1):
            time2[j]=1
    s=0
    for i in range(24):
        if time1[i]==time2[i] and time1[i]==1:
            s+=1
    print s