1118 Lining Up

Lining Up

Time Limit: 2000MS		Memory Limit: 32768K
Total Submissions: 13755		Accepted: 4238

Description

"How am I ever going to solve this problem?" said the pilot.

Indeed, the pilot was not facing an easy task. She had to drop packages at specific points scattered in a dangerous area. Furthermore, the pilot could only fly over the area once in a straight line, and she had to fly over as many points as possible. All points were given by means of integer coordinates in a two-dimensional space. The pilot wanted to know the largest number of points from the given set that all lie on one line. Can you write a program that calculates this number?


Your program has to be efficient!

Input

Input consist several case,First line of the each case is an integer N ( 1 < N < 700 ),then follow N pairs of integers. Each pair of integers is separated by one blank and ended by a new-line character. The input ended by N=0.

Output

output one integer for each input case ,representing the largest number of points that all lie on one line.

Sample Input

5
1 1
2 2
3 3
9 10
10 11
0

Sample Output

3

 

#include<iostream> using namespace std; int main() { int n,i; while(cin>>n,n!=0) { int x[1000],y[1000]; for(i=0;i<n;i++) { cin>>x[i]>>y[i]; } int j,f,sum,max=0; for(i=0;i<n;i++) { for(j=i+1;j<n;j++) { sum=0; for(f=i+1;f<n;f++) { if(((y[f]-y[i])*(x[j]-x[i]))==((x[f]-x[i])*(y[j]-y[i]))) { sum++; } } if(sum>max) { max=sum; } } } cout<<max+1<<endl; } return 0; }

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