poj 2236 Wireless Network

water

 

 

#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <vector>
using namespace std;
const int M = 1007;
int f[M],rnk[M],flg[M];
double x[M],y[M],d;
int n;
vector<int> g[M];

void init(int n) { for (int i = 0; i <= n; i++) { f[i] = i; rnk[i] = 0; flg[i] = 0;} }

int find(int x) { return x == f[x] ? x : f[x] = find(f[x]); }

void join(int x, int y){
    x = find(x), y = find(y);
    if(x != y){
        if(rnk[x] > rnk[y]) f[y] = x;
        else{
            f[x] = y;
            if(rnk[x] == rnk[y])
                rnk[y]++;
        }
    }
}
void solve(int x){
    for(int i=0;i<g[x].size();i++){
        if(flg[g[x][i]]) join(x,g[x][i]);
    }
}
int main(){
    freopen("1.in","r",stdin);
    freopen("1.out","w",stdout);
    scanf("%d%lf",&n,&d);
    for(int i=1;i<=n;i++) scanf("%lf%lf",&x[i],&y[i]);
    init(n+3);
    for(int i=1;i<=n;i++)
        for(int j=i+1;j<=n;j++){
            if(sqrt((x[i]-x[j])*(x[i]-x[j])+(y[i]-y[j])*(y[i]-y[j]))<=d){
                g[i].push_back(j);g[j].push_back(i);
            }
        }
    char op[2];int x,y;
    while(~scanf("%s",op)){
        if(op[0]=='O'){
            scanf("%d",&x);flg[x]=1;
            solve(x);
        }
        else{
            scanf("%d%d",&x,&y);
            if(find(x)==find(y)) printf("SUCCESS\n");
            else printf("FAIL\n");
        }
    }
    return 0;
}