t=int(raw_input())
while t>0:
	m,n=map(int,raw_input().strip().split())
	mlist=[]
	for i in range(m):#m
		m1,m2=map(int,raw_input().strip().split())
		for k in range(m1,m2+1):
			mlist.append(k)
	for mli in mlist:
		if mlist.count(mli)>1:
			mlist.remove(mli)
	nlist=[]
	for j in range(n):#n
		n1,n2=map(int,raw_input().strip().split())
		for k in range(n1,n2+1):
			nlist.append(k)
	for li in nlist:
		if nlist.count(li)>1:
			nlist.remove(li)
	c=0
	for li in mlist:
		if nlist.count(li)==1:
			c=c+1
	print c
	t=t-1