HDU 2586.How far away ？-离线LCA(Tarjan)

2586.How far away ？

这个题以前写过在线LCA(ST)的，HDU2586.How far away ？-在线LCA(ST)

现在贴一个离线Tarjan版的

代码:

 //A-HDU2586-LCA-tarjan离线版
 #include<iostream>
 #include<cstdio>
 #include<cstring>
 #include<algorithm>
 #include<bitset>
 #include<cassert>
 #include<cctype>
 #include<cmath>
 #include<cstdlib>
 #include<ctime>
 #include<deque>
 #include<iomanip>
 #include<list>
 #include<map>
 #include<queue>
 #include<set>
 #include<stack>
 #include<vector>
 using namespace std;
 typedef long long ll;

 const double PI=acos(-1.0);
 const double eps=1e-;
 const ll mod=1e9+;
 const int inf=0x3f3f3f3f;
 const int maxn=4e4+;
 const int maxm=+;
 #define ios ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);

 struct node{
     int x,y;
     //node(int xx,int yy){
     //    x=xx,y=yy;
     //}node(){}
 };

 vector<node> edge[maxn],q[maxn];
 int ans[maxn],dis[maxn],fa[maxn],vis[maxn];
 int n,m,aa,bb,cc;

 int find(int x)//找父节点(祖先)
 {
     return x==fa[x]?x:fa[x]=find(fa[x]);
 }

 void unio(int x,int y)//并查集压缩路径
 {
     fa[find(y)]=find(x);
 }

 void init()//初始化
 {
     for(int i=;i<=n;i++){
         edge[i].clear();
         q[i].clear();
         fa[i]=i;//初始化自己的父亲节点是自己
         vis[i]=;
         ans[i]=;
         dis[i]=;
     }
 }

 void dfs(int x)//tarjan
 {
     vis[x]=;
     for(int i=;i<edge[x].size();i++){
         int v=edge[x][i].x;
         if(!vis[v]){
             dis[v]=dis[x]+edge[x][i].y;
             dfs(v);
             unio(x,v);
         }
     }
     for(int i=;i<q[x].size();i++){
         int v=q[x][i].x;
         if(vis[v])
             ans[q[x][i].y]=dis[x]+dis[v]-*dis[find(v)];
     }
 }

 int main()
 {
     int T;
     scanf("%d",&T);
     while(T--){
         scanf("%d%d",&n,&m);
         init();
         for(int i=;i<n;i++){
             scanf("%d%d%d",&aa,&bb,&cc);
             //edge[aa].push_back(node(bb,cc));
             //edge[bb].push_back(node(aa,cc));
             edge[aa].push_back({bb,cc});
             edge[bb].push_back({aa,cc});
         }
         for(int i=;i<=m;i++){
             scanf("%d%d",&aa,&bb);
             //q[aa].push_back(node(bb,i));
             //q[bb].push_back(node(aa,i));
             q[aa].push_back({bb,i});
             q[bb].push_back({aa,i});

         }
         dfs();
         for(int i=;i<=m;i++)
         printf("%d\n",ans[i]);
     }
 }

溜了。