LightOJ 1123 - Trail Maintenance

#include <algorithm>
#include <bitset>
#include <cctype>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <fstream>
#include <iostream>
#include <list>
#include <map>
#include <memory>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <utility>
#include <vector>
#include <iomanip>

using namespace std;

#define REP(i,n) for(__typeof(n) i=0; i<(n); i++)
#define FOR(i,a,b) for(__typeof(b) i=(a); i<=(b); i++)
#define RESET(t,value) memset((t), value, sizeof(t))
typedef long long int64;
typedef long double d64;
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
#define PI acos(-1.0)
#define INF (1<<30)
#define eps 1e-8
#define pb push_back
#define ppb pop_back
#define pii pair<double,double>
#define G struct node

vector < int64 > pset(10000);
void initSet(int64 _size){ pset.resize(_size); FOR(i,0,_size) pset[i]=i;}
int64 findSet(int64 i){return (pset[i]== i)?i: (pset[i] = findSet(pset[i]));}
void unionSet(int64 i,int64 j){ pset[findSet(i)]=findSet(j);}
bool isSameSet(int64 i,int64 j){ return findSet(i)==findSet(j);}

#define Max 10000
G
{
    int64 u,v,cost;
    bool operator <(const G& a) const {
        return cost<a.cost;
    }
}g[Max+10];

vector <int64> v;

void reset()
{
    pset.clear();
    v.clear();
}

int64 mstree(int64 edge_no, int64 vertex_no)
{
    initSet(vertex_no+5);
    sort(g,g+edge_no);
    int64 mst = 0, count=0;
    REP(i,edge_no)
    {
        if(!isSameSet(g[i].u, g[i].v))
        {
            v.pb(g[i].cost);
            mst += g[i].cost;
            unionSet(g[i].u,g[i].v);
        }
    }
    if(v.size()!= vertex_no -1) mst = -1;
    return mst;
}


int main()
{
    //READ("1172.txt");
    int64 vertex_no, edge_no,airport_cost,mst;
    int t, caseNo=1;
    cin>>t;
    while(t--)
    {
        cin>>vertex_no>>edge_no;
        REP(i,edge_no) cin>>g[i].u>>g[i].v>>g[i].cost;
        cout<<"Case "<<caseNo<<":\n";
        FOR(i, 1, edge_no)
        {
            mst = mstree(i, vertex_no);
            cout<<mst<<endl;
            reset();
        }
        caseNo++;
    }
    return 0;
}