Лентяй (СКАНЛАЙН)

n = int(input())
a = []
for i in range(n):
    x, y = map(int, input().split())
    a.append((x, 1))
    a.append((y, 2))
a.sort()
b = 0
for i in range(2 * n):
    if a[i][1] == 1:
        b += 1
    else:
        b -= 1
    if b == n:
        print('YES')
        exit(0)
print('NO')