# -*- coding:utf-8 -*-

class Solution(object):

def maxPoints(self, points):

"""

:type points: List[List[int]]

:rtype: int

"""

# 大致思路是，每次拿出一个点，跟其他点比较。用一个dict来记录斜率相同的数目。

# 然后把某个斜率数目最大的值记录下来

def helper(currentPoint, points):

slopes, duplicates, ans = {}, 0, 0

x1, y1 = currentPoint

for x2, y2 in points:

# If the points are same inc duplicate counter

if x1 == x2 and y1 == y2:

duplicates += 1

# else find the slop and add in dic

else:

from fractions import Fraction

# 以分数的形式作为key存储而不是 小数

slope = Fraction(x2 - x1,y2 - y1) if y2 != y1 else 'inf'

count = slopes.get(slope, 0) + 1

slopes[slope] = count

ans = max(ans, count)

return ans + 1 + duplicates

ans = 0

while points:

currentPoint = points.pop()

ans = max(ans, helper(currentPoint, points))

return ans

if __name__ == "__main__":

r = Solution().maxPoints([[-4,1],[-7,7],[-1,5],[9,-25]])

print r