优美的链式前向星

首先贴上一份贴别好的blog详细的介绍了链式前向星的全过程：

链式前向星

贴上一份板子：

#include <bits/stdc++.h>using namespace std;const int maxn = 4e5+100;struct node{    int to, next, weight;}edge[maxn];int cnt;int head[maxn];int n;void add(int u, int v, int weight){    edge[cnt].to = v;    edge[cnt].weight = weight;    edge[cnt].next = head[u];    head[u] = cnt++;}int main(){    while(cin>>n){        cnt=0, memset(head, -1, sizeof(head));        for(int i=0; i<n-1; i++){            int u, v, weight;            cin>>u>>v>>weight;            add(u, v, weight);            add(v, u, weight);        }        for(int i=1; i<=n; i++){            for(int j=head[i]; j!=-1; j = edge[j].next){                cout<<edge[j].to<<" ";            }            cout<<endl;        }    }    return 0;}