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#include<cstdio>
#include<cmath>
#define NMAX 200200
#include<vector>
#include<algorithm>
using namespace std;
struct gf
{
int l,r;
};
vector<gf>sol;
vector<gf>v[NMAX];
int cost[NMAX],H[NMAX*2+100],Poz[NMAX],tata[NMAX];
int n,m,i,x,y,c,lg;
void apm(int nod)
{
vector<gf>::iterator it;
for(it=v[nod].begin();it!=v[nod].end();++it)
{
gf X=*it;
if (cost[X.l]>X.r) {cost[X.l]=X.r;tata[X.l]=nod;}
}
}
void pop(int poz)
{
while (poz>1 && cost[H[poz]]<cost[H[poz/2]])
{
swap(H[poz],H[poz/2]);
swap(Poz[H[poz]],Poz[H[poz/2]]);
poz=poz/2;
}
}
void bagaheap(int nod)
{
H[++lg]=nod;
Poz[nod]=lg;
pop(lg);
}
void push(int poz)
{
while ( (poz*2<=lg && cost[H[poz]]>cost[H[poz*2]])|| (poz*2+1<=lg+1 && cost[H[poz]]>cost[H[poz*2+1]]))
{
if (cost[H[poz*2]]<cost[H[poz*2+1]] || poz*2+1>lg)
{
swap(H[poz],H[poz*2]);
swap(Poz[H[poz]],Poz[H[poz*2]]);
poz=poz*2;
}
else
{
swap(H[poz],H[poz*2+1]);
swap(Poz[H[poz]],Poz[H[poz*2+1]]);
poz=poz*2+1;
}
}
}
int Minim()
{
int Min=H[1];
swap(H[1],H[lg]);
swap(Poz[H[1]],Poz[H[lg]]);
--lg;
push(1);
Poz[Min]=0;
return Min;
}
int main()
{
freopen("apm.in","r",stdin);
freopen("apm.out","w",stdout);
scanf("%d%d",&n,&m);
for (i=1;i<=m;++i)
{
scanf("%d%d%d",&x,&y,&c);
gf X; X.l=y,X.r=c;
v[x].push_back(X);
X.l=x;X.r=c;
v[y].push_back(X);
}
for (i=2;i<=m;++i) cost[i]=INFINITY;
cost[1]=0;
apm(1);
for (i=2;i<=n;++i)
{
bagaheap(i);
}
int sum=0;
for (i=1;i<n;++i)
{
int x=Minim();
apm(x);
sum+=cost[x];
gf X;X.l=x;X.r=tata[x];
sol.push_back(X);
vector<gf>::iterator it;
for (it=v[x].begin();it!=v[x].end();++it)
{
gf X=*it;
if (Poz[X.l]!=0) pop(Poz[X.l]);
}
}
printf("%d\n%d\n",sum,n-1);
vector<gf>::iterator it;
for (it=sol.begin();it!=sol.end();++it)
{
gf X=*it;
printf("%d %d\n",X.l,X.r);
}
return 0;
}