import sys


n = int(raw_input().strip())
x,y = raw_input().strip().split(' ')
firstx,firsty = [int(x),int(y)]
result = 'YES'
main_slope = None

for a0 in xrange(n-1):
    x,y = raw_input().strip().split(' ')
    x,y = [int(x),int(y)]
    if x-firstx != 0:
        slope = (y-firsty)/(x-firstx)
    else:
        slope = float('inf')
    if a0 == 0:
        main_slope = slope
    if slope != main_slope:
        result = 'NO'
        break
        
print result