hdu 1875 畅通工程再续

 1 #include "iostream"
 2 #include "algorithm"
 3 #include "cstdio"
 4 #include "cmath"
 5 using namespace std;
 6 #define MAXN 111
 7 
 8 struct loc{
 9     double a,b;
10 }q[MAXN];
11 
12 struct node{
13     int x,y;
14     double l;
15     int n;
16 }p[MAXN*MAXN];
17 
18 int fa[MAXN*MAXN];
19 int n, num;
20 double ans;
21 bool ok;
22 bool cmp(node x,node y)
23 {
24     return x.l < y.l; 
25 }
26 
27 void init()
28 {
29     num = 0;
30     ans = 0;
31     for (int i = 0;i < MAXN*MAXN; ++ i)
32         fa[i] = i,p[i].n = 1;
33 }
34 
35 int find(int x) 
36 {
37     return fa[x] = fa[x] == x ? x:find(fa[x]);
38 }
39 
40 void process()
41 {
42     init();
43     cin >> n;
44     for (int i = 0;i < n ; ++ i) 
45         cin >> q[i].a >> q[i].b;
46     for (int i = 0;i < n; ++ i)
47         for (int j = i+1;j < n; ++ j) {
48         p[num].x = i;
49         p[num].y = j;
50         double len =  sqrt((q[i].a - q[j].a)*(q[i].a - q[j].a) + (q[i].b - q[j].b)*(q[i].b- q[j].b));
51         if (len >= 10 && len <= 1000) {
52             p[num].l = len;
53             num++;
54             }
55         }
56         sort(p,p+num,cmp);
57         for (int i = 0; i < num ; ++ i) {
58             int x = find(p[i].x);
59             int y = find(p[i].y);
60             if (x != y) {
61                 fa[y] = x;
62                 ans += p[i].l*100;
63                 p[x].n += p[y].n;
64             }
65         }
66         int max = -1;
67         for (int i = 0;i < num; ++ i)
68             if (p[i].n > max) max = p[i].n;
69         if (max == n) printf("%.1lf\n",ans);
70         else cout << "oh!" << endl;
71 }
72 
73 int main()
74 {
75     int T;
76     cin >> T;
77     while (T--) {
78         process();
79     }
80     return 0;
81 }