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#include <bits/stdc++.h>
//#pragma GCC optimize ("03")
#define FastIO ios_base::sync_with_stdio(false) , cin.tie(0) , cout.tie(0)
#define FILES freopen("apm.in" , "r" , stdin) , freopen("apm.out" , "w" , stdout)
#define ll long long
#define ull unsigned long long
#define ld long double
#define eb emplace_back
#define pb push_back
#define qwerty1 first
#define qwerty2 second
#define qwerty3 -> first
#define qwerty4 -> second
#define umap unordered_map
#define uset unordered_set
#define pii pair < int , int >
#define pq priority_queue
#define dbg(x) cerr << #x << ": " << x << '\n'
namespace FastRead
{
char buff[5000];int lg = 0 , p = 0;
char nc()
{
if(lg == p){lg = fread(buff , 1 , 5000 , stdin);p = 0;if(!lg) return EOF;}
return buff[p++];
}
template<class T>void read(T&x)
{
T sgn = 1; char c;while(!isdigit(c = nc()))if(c == '-')sgn = -1;
x = c - '0';while(isdigit(c = nc()))x = x * 10 + c - '0';x *= sgn;
}
}
using namespace FastRead;
using namespace std;
const int N = 4e5 + 10;
const int M = 1e9 + 7;
const ld PI = acos(-1);
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int n , m , x , y , cost;
int root[N] , height[N];
vector < pii > answer;
struct ceva
{
int cost , x , y;
}a[N];
bool inline cmp(ceva a , ceva b)
{
return a.cost < b.cost;
}
int find(int x)
{
int R;
for(R = x ; R != root[R] ; R = root[R]);
for( ; root[x] != x ; )
{
int aux = root[x];
root[x] = R;
x = aux;
}
}
void unite(int rx , int ry)
{
if(height[rx] < height[ry])
root[rx] = ry;
else if(height[rx] > height[ry])
root[ry] = rx;
else
{
++height[ry];
root[rx] = ry;
}
}
signed main()
{
#ifndef ONLINE_JUDGE
FastIO , FILES;
#endif
int i;
cin >> n >> m;
for(i = 1 ; i <= m ; i++)
{
cin >> x >> y >> cost;
a[i] = {cost , x , y};
}
sort(a + 1 , a + m + 1 , cmp);
for(i = 1 ; i <= n ; i++)
{
root[i] = i;
height[i] = 1;
}
int sum = 0;
for(i = 1 ; i <= m ; i++)
{
int rx = find(a[i].x);
int ry = find(a[i].y);
if(rx != ry)
{
sum += a[i].cost;
answer.pb({a[i].x , a[i].y});
unite(rx , ry);
}
}
cout << sum << '\n';
cout << answer.size() << '\n';
for(auto i : answer)
cout << i.first << ' ' << i.second << '\n';
return 0;
}