//Prim
#include <bits/stdc++.h>
using namespace std;

class Reader{
    public:
        Reader() {}
        Reader(const char *file_name){
            input_file.open(file_name,std::ios::in | std::ios::binary);
            input_file.sync_with_stdio(false);
            index&=0;
            input_file.read(buffer,SIZE);}
        inline Reader &operator >>(int &n){
            for (;buffer[index]<'0' or buffer[index]>'9';inc());
            n&=0;
            sign&=0;
            sign|=(buffer[index-1]=='-');
            for (;'0'<=buffer[index] and buffer[index]<='9';inc())
                n=(n<<1)+(n<<3)+buffer[index]-'0';
            n^=((n^-n)&-sign);
            return *this;}
        ~Reader(){
            input_file.close();}
    private:
        std::fstream input_file;
        static const int SIZE=0x400000;
        char buffer[SIZE];
        int index,sign;
        inline void inc(){
            if(++index==SIZE)
                index=0,input_file.read(buffer,SIZE);}
};

class Writer{
    public:
        Writer() {};
        Writer(const char *file_name){
            output_file.open(file_name,ios::out | ios::binary);
            output_file.sync_with_stdio(false);
            index=0;}
        inline Writer &operator <<(int target){
            aux=0;
            n=target;
            if (target<0)
                sign=-1;
            else
                sign=1;
            if (!n)
                nr[aux++]='0';
            for (;n;n/=10)
                nr[aux++]=sign*(n%10)+'0';
            if (sign==-1){
                buffer[index]='-';inc();}
            for(;aux;inc())
                buffer[index]=nr[--aux];
            return *this;}
        inline Writer &operator <<(const char *target){
            aux=0;
            while (target[aux])
                buffer[index]=target[aux++],inc();
            return *this;}
        ~Writer(){
            output_file.write(buffer,index);output_file.close();}
    private:
        fstream output_file;
        static const int SIZE=0x200000;
        int index=0,aux,n,sign;
        char buffer[SIZE],nr[24];
        inline void inc(){
            if(++index==SIZE)
                index=0,output_file.write(buffer,SIZE);}
};

Reader f ("apm.in");
Writer g ("apm.out");

struct Edge
{
    int x,y,c;
    Edge(int _x = 0,int _y = 0,int _c = 0)
    {
        x = _x;
        y = _y;
        c = _c;
    }
    bool operator ()(Edge a,Edge b)
        {
            return a.c > b.c;
        }
};

int N,M,costArb;
int Distance[200001];
bitset<200001> Visited;
priority_queue<Edge,vector<Edge>,Edge> Q;
vector<Edge> G[200001];
vector<Edge> Sol;

void read_data()
{
    f>>N>>M;
    for (int i=1; i<=M; ++i)
    {
        int x,y,c;
        f>>x>>y>>c;
        G[x].push_back(Edge(x,y,c));
        G[y].push_back(Edge(y,x,c));
    }
}

void init()
{
    Distance[1] = 0;
    for (int i=2; i<=N; ++i) Distance[i] = INT_MAX;
}

void APM()
{
    Q.push(Edge(0,1,0));
    while (!Q.empty())
    {
        Edge now = Q.top();
        Q.pop();

        int node = now.y;
        if (Distance[node] < now.c)
        {
            continue;
        }
        Visited[node] = true;
        costArb += now.c;
        Sol.push_back(now);

        for (auto it:G[node])
        {
            int next=it.y;
            int cost=it.c;
            if (Visited[next]==0 && Distance[next] > cost)
            {
                Distance[next] = cost;
                Q.push(Edge(node,next,cost));
            }
        }
    }
}

void write_data()
{
    g<<costArb<<"\n"<<Sol.size()-1<<"\n";
    for (int k=1; k < Sol.size(); ++k)
        g<<Sol[k].x<<" "<<Sol[k].y<<"\n";
}

int main()
{
    read_data();
    init();
    APM();
    write_data();
}