zoj 1542 Network

/**************************************************************************
user_id: SCNU20102200088
problem_id: zoj 1542
problem_name: Network
**************************************************************************/

#include <algorithm>
#include <iostream>
#include <iterator>
#include <iomanip>
#include <sstream>
#include <fstream>
#include <cstring>
#include <cstdlib>
#include <climits>
#include <bitset>
#include <string>
#include <vector>
#include <cstdio>
#include <cctype>
#include <ctime>
#include <cmath>
#include <queue>
#include <stack>
#include <list>
#include <set>
#include <map>
using namespace std;

//线段树
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1

//手工扩展栈
#pragma comment(linker,"/STACK:102400000,102400000")

const double EPS=1e-9;
const double PI=acos(-1.0);
const double E=2.7182818284590452353602874713526;  //自然对数底数
const double R=0.5772156649015328606065120900824;  //欧拉常数:(1+1/2+...+1/n)-ln(n)

const int x4[]={-1,0,1,0};
const int y4[]={0,1,0,-1};
const int x8[]={-1,-1,0,1,1,1,0,-1};
const int y8[]={0,1,1,1,0,-1,-1,-1};

typedef long long LL;

typedef int T;
T max(T a,T b){ return a>b? a:b; }
T min(T a,T b){ return a<b? a:b; }
T gcd(T a,T b){ return b==0? a:gcd(b,a%b); }
T lcm(T a,T b){ return a/gcd(a,b)*b; }

///////////////////////////////////////////////////////////////////////////
//Add Code:
int n,s[1005];

struct Node{
int u,v,w;
bool operator <(const Node &a) const{
return w>a.w;
}
}node;

priority_queue<Node> pq;

void Union(int x,int y){
s[y]=x;
}

int Find(int x){
if(s[x]<0) return x;
return s[x]=Find(s[x]);
}

void Kruskal(){
int num=0,ret=0,i,x[1005],y[1005];
memset(s,-1,sizeof(s));
while(!pq.empty() && num<n-1){
node=pq.top();
pq.pop();
if(Find(node.u)!=Find(node.v)){
Union(Find(node.u),Find(node.v));
ret+=node.w;
num++;
x[num]=node.u;
y[num]=node.v;
}
}
printf("%d\n",node.w);
printf("%d\n",num);
for(i=1;i<=num;i++) printf("%d %d\n",x[i],y[i]);
while(!pq.empty()) pq.pop();
}
///////////////////////////////////////////////////////////////////////////

int main(){
std::ios::sync_with_stdio(false);
//freopen("in.txt","r",stdin);
//freopen("out.txt","w",stdout);
///////////////////////////////////////////////////////////////////////
//Add Code:
int m,i;
while(scanf("%d%d",&n,&m)!=EOF){
for(i=1;i<=m;i++){
scanf("%d%d%d",&node.u,&node.v,&node.w);
pq.push(node);
}
Kruskal();
}
///////////////////////////////////////////////////////////////////////
return 0;
}

/**************************************************************************
Testcase:
Input:
4 6
1 2 1
1 3 1
1 4 2
2 3 1
3 4 1
2 4 1
Output:
1
3
1 2
2 4
1 3
**************************************************************************/