import sys
T=int(input())
for _ in range(T):
N=int(input())
L=[ [0,0] for i in range(N) ]
for i in range(N):
L[i][0],L[i][1] = map(int,sys.stdin.readline().split())
L.sort()
new_worker=0
max_rank=L[0][1]
for i in range(N):
if L[i][1] <= max_rank:
new_worker += 1
max_rank=L[i][1]
print(new_worker)