Poj Solution 1861

http://poj.org/problem?id=1861

//* @author: ccQ.SuperSupper
import java.io.*;
import java.util.*;
class Edge implements Comparable{
    int u,v,disten;
    Edge(){};
    void set(int u,int v,int disten){
        this.u = u;
        this.v = v;
        this.disten = disten;
    }
    public int compareTo(Object obj){
        Edge temp = (Edge)obj;
        if(this.disten>temp.disten) return 1;
        return -1;
    }
}
class Set{
    int father[],num[];
    void init(int n){
        num = new int[n+10];
        father = new int[n+10];
        Arrays.fill(num, 1);
        Arrays.fill(father, -1);
    }
    int Ufind(int who){
        int temp,cnt = who;
        while(father[who]!=-1){
            who = father[who];
        }
        while(cnt!=who){
            temp = father[cnt];
            father[cnt] = who;
            cnt = temp;
        }
        return who;
    }
    void Uset(int u,int v){
        if(u==v) return ;
        if(num[u]>num[v]){
            father[v] = u;
            num[u]+=num[v];
        }else{
            father[u] = v;
            num[v]+=num[u];
        }
    }
}
class Kruscal{
    final int N = 15000+100;
    int n,m,cnt,max,ans;
    Edge edge[] = new Edge[N];
    Kruscal(){
        for(int i=0;i< N;++i) edge[i] = new Edge();
    }
    void init(int n,int m){
        cnt = 0;
        this.n = n;
        this.m = m;
        max = ans = 0;
    }
    void addEdge(int u,int v,int disten){
        edge[cnt++].set(u, v, disten);
    }
    void calc(PrintWriter out){
        Set set = new Set();
        set.init(n);
        Arrays.sort(edge,0,m);
        for(int i=0;i< m;++i){
            if(set.Ufind(edge[i].u) == set.Ufind(edge[i].v)){
                edge[i].disten = -1;
            }else{
                max = Max(max,edge[i].disten);
                ++ans;
                set.Uset(set.Ufind(edge[i].u), set.Ufind(edge[i].v));
            }
        }
        
        out.println(max);
        out.println(ans);
        for(int i=0;i< m;++i)if(edge[i].disten>=0){
            out.println(edge[i].u+" "+edge[i].v);
        }
    }
    int Max(int a,int b){
        return a>b?a:b;
    }
}
public class Main {
 public static void main(String[]args)throws Exception{
  StreamTokenizer cin = new StreamTokenizer(new BufferedReader(new InputStreamReader(System.in)));
    PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out));
    Kruscal kruscal = new Kruscal();
    int n,m,u,v,disten;
    n = GetNum(cin);
    m = GetNum(cin);
    kruscal.init(n, m);
    for(int i=0;i< m;++i){
        u = GetNum(cin);
        v = GetNum(cin);
        disten = GetNum(cin);
        if(u>v) kruscal.addEdge(v, u, disten);
        else kruscal.addEdge(u, v, disten);
    }
    kruscal.calc(out);
    out.flush();
 }
    static int GetNum(StreamTokenizer cin)throws Exception{
        cin.nextToken();
        return (int) cin.nval;
    }
}

											
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