def pendiente(x1, y1, x2, y2):
	if x2 - x1 == 0:
		return 0
	else:
		return (y2 - y1) / (x2 - x1)

n = int(input().strip())
x1, y1 = map(int, input().split())
aux = True
for i in range(n - 1):
	x2, y2 = map(int, input().split())
	if pendiente(x1, y1, x2, y2) != 0:
		print('NO')
		aux = False
		break
	x1, y1 = x2, y2

if aux:
		print('YES')