POJ2236(Wireless Network)

                                                                                                                                 Wireless Network

Time Limit: 10000MS Memory Limit: 65536KTotal Submissions: 22345 Accepted: 9387

Description

An earthquake takes place in Southeast Asia. The ACM (Asia Cooperated Medical team) have set up a wireless network with the lap computers, but an unexpected aftershock attacked, all computers in the network were all broken. The computers are repaired one by one, and the network gradually began to work again. Because of the hardware restricts, each computer can only directly communicate with the computers that are not farther than d meters from it. But every computer can be regarded as the intermediary of the communication between two other computers, that is to say computer A and computer B can communicate if computer A and computer B can communicate directly or there is a computer C that can communicate with both A and B.

In the process of repairing the network, workers can take two kinds of operations at every moment, repairing a computer, or testing if two computers can communicate. Your job is to answer all the testing operations.

Input

The first line contains two integers N and d (1 <= N <= 1001, 0 <= d <= 20000). Here N is the number of computers, which are numbered from 1 to N, and D is the maximum distance two computers can communicate directly. In the next N lines, each contains two integers xi, yi (0 <= xi, yi <= 10000), which is the coordinate of N computers. From the (N+1)-th line to the end of input, there are operations, which are carried out one by one. Each line contains an operation in one of following two formats:
1. "O p" (1 <= p <= N), which means repairing computer p.
2. "S p q" (1 <= p, q <= N), which means testing whether computer p and q can communicate.

The input will not exceed 300000 lines.

Output

For each Testing operation, print "SUCCESS" if the two computers can communicate, or "FAIL" if not.

Sample Input

4 10 10 20 30 4O 1O 2O 4S 1 4O 3S 1 4

Sample Output

FAILSUCCESS题意分析：一张图上分布着n台坏了的电脑，并知道它们的坐标。两台修好的电脑如果距离<=d就可以联网，也可以通过其他修好的电脑间接相连。给出操作“O x”表示修好x，给出操作“S x y”，请你判断x和y在此时有没有联网 代码：
#include<iostream>#include<cmath>#include<cstring>#include<stdio.h>using namespace std;#define M 1002int date[M];int set[M],pos[M][2];double arc[M][M];int find(int x){ if(x!=date[x])  date[x]=find(date[x]); return date[x];}void setunion(int x,int y){ int a=find(x); int b=find(y); if(a!=b)  date[a]=b;}int main(){ int i,j; int N,D;  char ch; int p,q; while(scanf("%d%d",&N,&D)!=EOF) {  memset(set,0,sizeof(set));    for(i=1;i<=N;i++)   date[i]=i;    for(i=1;i<=N;i++)   scanf("%d%d",&pos[i][0],&pos[i][1]);    for(i=1;i<=N;i++)   for(j=1;j<=N;j++)    arc[i][j]=double(sqrt( double( pow(pos[i][0]-pos[j][0],2) + pow(pos[i][1]-pos[j][1],2) ) ));      while(scanf("%s",&ch)!=EOF)   {        if(ch=='O')    {     cin>>p;     set[p]=1;     for(i=1;i<=N;i++)     {          if(set[i]&&arc[p][i]<=D)       setunion(p,i);     }    }    else    {     scanf("%d%d",&p,&q);     if(find(p)==find(q))      printf("SUCCESS\n");     else      printf("FAIL\n");    }   } } return 0;}