member = []
for _ in range(int(input())):
    a, b = map(int, input().split())
    member.append([a, b])
item = []
for _ in range(int(input())):
    a, b = map(int, input().split())
    item.append([a, b, 0])
for [a, b] in member:
    for i in range(len(item)):
        x, y, z = item[i]
        if a >= x and b <= y:
            item[i] = [x, y, 1]
count = 0
for i in item:
    x, y, z = i
    if z == 1:
        count += 1
print(count)