POJ2236 Wireless Network 并查集

#include<cstdio>

#include<cstring>

#include<queue>

#include<set>

#include<cstdlib>

#include<algorithm>

#include<vector>

#include<cmath>

using namespace std;

typedef long long LL;

typedef pair<int,int>pii;

const int N=1e3+;

const int INF=0x3f3f3f3f;

pii o[N];

bool vis[N];

int fa[N];

int find(int x){

   return fa[x]==x?x:fa[x]=find(fa[x]);

}

int dis(int i,int j){

   return (o[i].first-o[j].first)*(o[i].first-o[j].first)+(o[i].second-o[j].second)*(o[i].second-o[j].second);

}

int main(){

    int n,d,x,y;

    scanf("%d%d",&n,&d);

    for(int i=;i<=n;++i)

        scanf("%d%d",&o[i].first,&o[i].second),fa[i]=i;

    char s[];

    while(~scanf("%s",s)){

        if(s[]=='O'){

          scanf("%d",&x);

          if(vis[x])continue;

          for(int i=;i<=n;++i){

            if(!vis[i]||dis(x,i)>d*d)continue;

            int u=find(x),v=find(i);

            if(u!=v)fa[u]=v;

          }

          vis[x]=true;

        }

        else {

          scanf("%d%d",&x,&y);

          x=find(x),y=find(y);

          if(x==y)printf("SUCCESS\n");

          else printf("FAIL\n");

        }

    }

    return ;

}