利用到的数据结构

struct eage{ll v,w;};//存储重点和，边权 vector e[N];//数组下标作为起点 ll n,m; bool vis[N];//判断是否走过 

#include   using namespace std; typedef long long ll; typedef double db; typedef long double ldb; typedef pair pii; typedef pair PII; #define pb emplace_back //#define int ll #define all(a) a.begin(),a.end() #define x first #define y second #define ps push_back #define endl '\n' #define IOS ios::sync_with_stdio(0),cin.tie(0),cout.tie(0)  void solve();  const int N = 1e6 + 10;   signed main() {     IOS;     solve();     return 0; }  struct eage{ll v,w;}; vector e[N]; ll n,m; bool vis[N];  void dfs(ll u) {     vis[u] = 1;     for(auto it : e[u])     {         ll v = it.v , w = it.w;         cout << u << " " << v << ' ' << w << endl;         if(vis[v]) continue;         dfs(v);     } }  void solve() {     cin >> n >> m;     for(int i = 1; i <= m; ++ i)     {         ll u,v,w;         cin >> u >> v >> w;         e[u].ps({v,w});     }     dfs(1); }  //输入 //7 6 //4 3 90 //1 4 30 //5 7 80 //5 6 60 //1 5 20 //5 2 70  //输出 //1 4 30 //4 3 90 //1 5 20 //5 7 80 //5 6 60 //5 2 70