kuangbin专题五、并查集

 1 #include<iostream>
 2 #include<cstdio>
 3 using namespace std;
 4 
 5 int n,d;
 6 int x[1005],y[1005];
 7 int vis[1005],fa[1005];
 8 
 9 bool ind(int a,int b)
10 {
11     return (x[a]-x[b])*(x[a]-x[b])+(y[a]-y[b])*(y[a]-y[b])<=d*d;
12 }
13 int find(int x)
14 {
15     if(fa[x]!=x) fa[x]=find(fa[x]);
16     return fa[x];
17 }
18 void unin(int a,int b)
19 {
20     int x=find(a);
21     int y=find(b);
22     if(x!=y) fa[x]=y;
23     return;
24 }
25 int main()
26 {
27     while(~scanf("%d%d",&n,&d))
28     {
29         for(int i=1;i<=n;i++)
30         {
31             scanf("%d%d",&x[i],&y[i]);
32             fa[i]=i;
33             vis[i]=0;
34         }
35         char s[2];
36         int a,b;
37         while(scanf("%c",&s)!=EOF)
38         {
39             if(s[0]==‘O‘)
40             {
41                 scanf("%d",&a);
42                 vis[a]=1;
43                 for(int i=1;i<=n;i++)
44                     if(vis[i] && ind(a,i) && i!=a)
45                         unin(i,a);
46             }
47             if(s[0]==‘S‘)
48             {
49                 scanf("%d%d",&a,&b);
50                 if(find(a)==find(b)) puts("SUCCESS");
51                 else puts("FAIL");
52             }
53         }
54     }
55     return 0;
56 }