poj 2236 Wireless Network(并查集)

/*  xzppp  */
#include <iostream>
#include <vector>
#include <cstdio>
using namespace std;
#define FFF freopen("in.txt","r",stdin);freopen("out.txt","w",stdout);
#define lson MAXN,m,rt<<1
#define rson m+1,r,rt<<1|1
#define MP make_pair
#define PB push_back
typedef long long  ll;
typedef unsigned long long ULL;
const int MAXN = 1000+17;
const int MAXM = 20;
const int INF = 0x7fffffff;
const int MOD = 1e9+7;
int par[MAXN],rk[MAXN];
int fd(int x)
{
if(par[x]==x)
return x;
else
return par[x] = fd(par[x]);
}
void unite(int x,int y)
{
int a = fd(x);
int b = fd(y);
if(a==b) return;
if(rk[a]>rk[b])
par[b] = a;
else
par[a] = b;
if(rk[a]==rk[b])
rk[a]++;
}
struct point
{
double x,y;
int id;
}all[MAXN];
int main(int argc, char const *argv[])
{
//FFF
double n,m;
cin>>n>>m;
m*=m;
for (int i = 0; i < n; ++i)
{
par[i] = i;
rk[i] = 0;
}
for (int i = 0; i < n; ++i)
{
scanf("%lf%lf",&all[i].x,&all[i].y);
all[i].id = i;
}
char cmd[10];
vector<point> v;
while(scanf("%s",cmd)!=EOF)
{
if(cmd[0]=='O')
{
int id;
scanf("%d",&id);
id--;
double a = all[id].x;
double b = all[id].y;
for (int i = 0; i < v.size(); ++i)
{
double x = v[i].x,y = v[i].y;
double dis = (x-a)*(x-a) + (y-b)*(y-b);
if(dis<=m)
unite(v[i].id, id);
}
v.PB(all[id]);
}
else
{
int a,b;
scanf("%d%d",&a,&b);
a--;b--;
if(fd(a)==fd(b))
puts("SUCCESS");
else
puts("FAIL");
}
}
return 0;
}