Clarke and five-pointed star

Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 472 Accepted Submission(s): 249

Problem Description

Clarke is a patient with multiple personality disorder. One day, Clarke turned into a learner of geometric.

When he did a research with polygons, he found he has to judge if the polygon is a five-pointed star at many times. There are 5 points on a plane, he wants to know if a five-pointed star existed with 5 points given.

Input

The first line contains an integer

T(1≤T≤10) , the number of the test cases.

For each test case, 5 lines follow. Each line contains 2 real numbers

xi,yi(−109≤xi,yi≤109) , denoting the coordinate of this point.

Output

Two numbers are equal if and only if the difference between them is less than

10−4 .

For each test case, print

Yes if they can compose a five-pointed star. Otherwise, print

No . (If 5 points are the same, print

Yes . )

Sample Input

23.0000000 0.00000000.9270509 2.85316950.9270509 -2.8531695-2.4270509 1.7633557-2.4270509 -1.76335573.0000000 1.00000000.9270509 2.85316950.9270509 -2.8531695-2.4270509 1.7633557-2.4270509 -1.7633557

Sample Output

YesNo   
       
         
     Hint

Source

#include 
    
     #include 
     
      #include 
      
       #include 
       
        using namespace std;double length[5][5];double point[5][2];const double MIN=1e-4;int main(){	int t,i,j;	scanf("%d",&t);	while(t--){		bool ok=1;		for(i=0;i<5;i++)			scanf("%lf%lf",&point[i][0],&point[i][1]);		for(i=0;i<5;i++){			for(j=0;j<5;j++){				if(i==j){					length[i][j]=0.0;					continue;				}				  				length[i][j]=(point[i][0]-point[j][0])*				(point[i][0]-point[j][0])+(point[i][1]-point[j][1])*				(point[i][1]-point[j][1]);							}			sort(length[i],length[i]+5);		}	/*	for(i=0;i<5;i++){		   printf("%0.6lf\n",length[i][1]);		}*/		for(i=1;i<5;i++){			//printf("%0.6lf\n",fabs(length[0][1]-length[i][1]));			if(fabs(length[0][1]-length[i][1])>MIN)			  ok=0;		}		if(ok)		  printf("Yes\n");		else		 printf("No\n");	}	return 0;}