#include using namespac

#includeusing namespace std;const int V=100;int n,m,ans,e[V][V];bool visited[V];void dfs(int x,int len){\tint i;\tvisited[x]= true;\tif(len>ans)\t\tans=len;\tfor(i=1;i<=n;i  )\t\tif( (!visited[i]) && (e[x][i]!=-1) )\t\t\tdfs(i,len e[x][i]);\tvisited[x]=false;}int main(){\tint i,j,a,b,c;\tcin>>n>>m;\tfor(i=1;i<=n;i  )\t\tfor(j=1;j<=m;j  )\t\t\te[i][j]=-1;\tfor(i=1;i<=m;i  )\t{\t\tcin>>a>>b>>c;\t\te[a][b]=c;\t\te[b][a]=c;\t}\tfor(i=1;i<=n;i  )\t\tvisited[i]=false;\tans=0;\tfor(i=1;i<=n;i  )\t\tdfs(i,0);\tcout<
输入：
4 6
1 2 10
2 3 20
3 4 30
4 1 40
1 3 50
2 4 60 
输出：