https://www.acmicpc.net/problem/7568
import sys
n = int(sys.stdin.readline().rstrip())
arr = []
for _ in range(n):
temp = list(map(int, sys.stdin.readline().rstrip().split()))
arr.append(temp)
for i in arr:
cnt = 1
for j in arr:
if i[0] < j[0] and i[1] < j[1]:
cnt += 1
print(cnt)