import sys, math


n = int(raw_input().strip())
x1,y1 = raw_input().strip().split(' ')
x1,y1 = [int(x1),int(y1)]
m = 0
flag = 0
for a0 in xrange(n-1):
    x2,y2 = raw_input().strip().split(' ')
    x2,y2 = [int(x2),int(y2)]
    if x1 != x2:
        m = math.tan((y2 - y1) / ( x2 - x1))
    else:
        m = 90
    if flag == 0:
        prev_m = m
        flag = 1
    if prev_m != m:
        print("NO")
        sys.exit(0)
    x1 = x2
    y1 = y2
print("YES")