#include <cstdio> #include <cstring> #include <algorithm> #include <climits> #include <string> #include <iostream> #include <map> #include <cstdlib> #include <list> #include <set> #include <queue> #include <stack> using namespace std; int father[22222]; int getfather(int x) { if(x!=father[x]) return father[x]=getfather(father[x]); return father[x]; } struct Node { int a;int b;int c; }node[111111]; int cmp(const Node&a,const Node &b) { return a.c<b.c; } int Max(int a,int b) { return a>b?a:b; } int gg[111111]; int Map[1111][1111]; int main() { int n,m; while(~scanf("%d%d",&n,&m)){ int ans=0; int sum=0; memset(Map,0,sizeof(Map)); for(int i=1;i<=n;i++) father[i]=i; for(int i=0;i<m;i++){ int a,b,c; scanf("%d%d%d",&a,&b,&c); if(!Map[a][b]){ Map[a][b]=Map[b][a]=c; node[ans].a=a;node[ans].b=b;node[ans++].c=c; } if(Map[a][b]&&Map[a][b]>c){ Map[a][b]=Map[b][a]=c; node[ans].a=a;node[ans].b=b;node[ans++].c=c; } } sort(node,node+ans,cmp); // cout<<endl; // for(int i=0;i<n;i++) // printf("%d %d %d ",node[i].a,node[i].b,node[i].c); int cc=0; int ret=0; for(int i=0;i<ans;i++){ int fa=getfather(node[i].a);int fb=getfather(node[i].b); if(fa!=fb){ father[fa]=fb;ret=Max(ret,node[i].c); gg[cc++]=i; } } cout<<ret<<endl; cout<<cc<<endl; for(int i=0;i<cc;i++){ printf("%d %d ",node[gg[i]].a,node[gg[i]].b); } } return 0; }