# Poj Solution 2780

```http://poj.org/problem?id=2780

//* @author: ccQ.SuperSupper
import java.io.*;
import java.util.*;
class Point implements Comparable {
double x,y;
public int compareTo(Object obj){
Point temp = (Point) obj;
if(temp.x!=this.x){
if(temp.x< this.x) return 1;
return -1;
}
if(temp.y< this.y) return 1;
return -1;
}
}
public class Main {
static final int N = 1000+10;
static int n;
static double p[] = new double[N];
static Point point[] = new Point[N];
static void start(){
for(int i=0;i< N;++i)
point[i] = new Point();
}

public static void main(String[]args) throws Exception{
int i;
start();

while(cin.nextToken()!=StreamTokenizer.TT_EOF){
n = (int) cin.nval;
for(i=0;i< n;++i){
cin.nextToken();
point[i].x = cin.nval;
cin.nextToken();
point[i].y = cin.nval;
}
if(n<=2) System.out.println(n);
else System.out.println(solve());
}
}

public static int solve(){
int i,j,k,cnt,ans=1;
Arrays.sort(point,0,n);
for(i=0;i< n;++i){
for(k=0,j=i+1;j< n;++j){
if(point[i].x==point[j].x)
p[k++] = 10000000000.0;
else
p[k++] = (point[j].y-point[i].y)/(point[j].x-point[i].x);
}
Arrays.sort(p,0,k);
cnt = 1;
//for(j=0;j< k;++j) System.out.print(p[j]+" ");System.out.println();
for(j=1;j< k;++j){
if(p[j]==p[j-1])
++cnt;
else{
ans = cnt>ans?cnt:ans;
cnt = 1;
}
}
ans = cnt>ans?cnt:ans;
}
return ans+1;
}
}

```
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