CSP/NOIP 可以用这种存图方式吗?
const int N = 1e5 + 5;
vector< pair<int, int> > g[N];
int n; cin >> n;
for (int i = 1, u, v, w; i < n; i++)
{
cin >> u >> v >> w;
g[u].push_back(make_pair(v, w));
g[v].push_back(make_pair(u, w));
}
int u = 1;
for (auto [v, w] : g[u])
{
}