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 0Sample Output
3 最多有多少个点在一条直线上 code： #include<cstdio> #include<algorithm> using namespace std; struct dian{ int x; int y; }a[800]; int main() { int n; while(~scanf("%d",&n)&&n!=0){ for(int i=1;i<=n;i++) scanf("%d%d",&a[i].x,&a[i].y); int sum=0,num; for(int i=1;i<=n;i++){ for(int j=i+1;j<=n;j++) { num=0; for(int k=j+1;k<=n;k++) { if((a[i].x-a[k].x)*(a[j].y-a[k].y)==(a[i].y-a[k].y)*(a[j].x-a[k].x)) num++; } sum=max(sum,num); } } printf("%d\n",sum+2); } return 0; }