leetcode 149. Max Points on a Line

Given n points on a 2D plane, find the maximum number of points that lie on the same straight line.

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思路
给出平面上的几个点，求出同在一条直线上的点最多的个数
两个for循环，求两个点之间的斜率，注意垂直于x轴的斜率的表示以及覆盖点的个数[0,0]和[0,0]是两个点

class Point(object):    def __init__(self,a=0,b=0):        self.x=a        self.y=bclass Solution(object):    def maxPoints(self,points):        Lenth=len(points)        if not Lenth:            return 0        Max_=0        for i in range(Lenth-1):            dict={}            count=0            for j in range(i+1,Lenth):                if points[i].x-points[j].x==0:                    if points[i].y==points[j].y:                        count=count+1                        dict.setdefault('b',0)                    else:                        if 'a' not in dict:                            dict.setdefault('a',1)                        else:                            dict['a']=dict['a']+1                else:                    k=(points[j].y-points[i].y)*1.0/(points[j].x-points[i].x)                    if k not in dict:                        dict.setdefault(k,1)                    else:                        dict[k]=dict[k]+1                #print dict            Max_=max(Max_,max(dict.items(),key=lambda x:x[1])[1]+count)        return (Max_+1)