hdu 5206 判断三维空间中的四个点是否构成正方形

 1 #include <algorithm>
 2 #include <iostream>
 3 #include <string>
 4 using namespace std;
 5 
 6 const int N = 4;
 7 
 8 struct Node 
 9 {
10     int x, y, z;
11 } node[N];
12 
13 inline long long square( int k )
14 {
15     return ( long long ) k * k;
16 }
17 
18 long long list[N];
19 
20 long long dis( Node a, Node b )
21 {
22     return square( a.x - b.x ) + square( a.y - b.y ) + square( a.z - b.z );
23 }
24 
25 bool solve()
26 {
27     for ( int i = 0; i < 4; i++ )
28     {
29         int cnt = 0;
30         for ( int j = 0; j < 4; j++ )
31         {
32             if ( i == j ) continue;
33             list[cnt++] = dis( node[i], node[j] );
34         }
35         sort( list, list + cnt );
36         if ( list[0] == list[1] && list[1] * 2 == list[2] ) {}
37         else return false;
38     }
39     return true;
40 }
41 
42 int main ()
43 {
44     int t;
45     cin >> t;
46     for ( int _case = 1; _case <= t; _case++ )
47     {
48         for ( int i = 0; i < 4; i++ )
49         {
50             cin >> node[i].x >> node[i].y >> node[i].z;
51         }
52         cout << "Case #" << _case << ": " << ( solve() ? "Yes" : "No" ) << endl;
53     }
54     return 0;
55 }