poj3592Instantaneous Transference（tarjan+spfa)

http://poj.org/problem?id=3592提交了30多次了 受不了了 两份的代码基本上一样了 一个AC一个WA 木办法 贴份别人的吧 改得跟我得一样 人家能A  我是WA。。

强连通分量缩点 用spfa算出最长路 注意算强连通时加过的值就不再加了

 #include <cstdio>
 #include <cstring>
 #include <iostream>
 #include <vector>
 #include <queue>
 #include<stack>
 using namespace std;
 const int NN=;
 const int MM=;
 const int INF=0x3fffffff;

 int n,m,w[NN],val[NN];
 char c[][];
 vector<int> adj[NN];

 struct Edge{
     int u,v,next;
 }edge[MM];
 int t,head[NN];
 void addedge(int u,int v)
 {
     edge[t].u=u;
     edge[t].v=v;
     edge[t].next=head[u];
     head[u]=t++;
 }

 int bcnt,top,depth,dfn[NN],low[NN],belong[NN],vis[NN],instack[NN];
 //bool instack[NN];
 stack<int>s;
 void init()
 {
     t=;
     memset(head,-,sizeof(head));
 }
 void tarjan(int u)
 {
     dfn[u]=low[u]=++depth;
     s.push(u);
     instack[u] = ;
     int v;
     for (int i=head[u]; i!=-; i=edge[i].next)
     {
         v=edge[i].v;
         if (!dfn[v])
         {
             tarjan(v);
             low[u]=min(low[u],low[v]);
         }
         else if (instack[v])
             low[u]=min(low[u],dfn[v]);
     }
     if (low[u]==dfn[u])
     {bcnt++;
         val[bcnt] = ;
         adj[bcnt].clear();
         for(;;)
         {
             v=s.top();
             s.pop();
             belong[v]=bcnt;
             val[bcnt]+=w[v];instack[v] = ;
             if(v==u)
             break;
         }

     }
 }
 int dis[NN];
 int lpfa(int S)
 {
     for (int i=; i<=bcnt; i++) dis[i]=-INF;
     memset(vis,,sizeof(vis));
     dis[S]=;
     queue<int> q;
     q.push(S);
     while (!q.empty())
     {
         int u=q.front();
         vis[u]=;
         q.pop();
         for (int i=; i<adj[u].size(); i++)
         {
             int v=adj[u][i];
             if (dis[v]<dis[u]+val[v])
             {
                 dis[v]=dis[u]+val[v];
                 if (!vis[v])
                 {
                     vis[v]=;
                     q.push(v);
                 }
             }
         }
     }
     int ret=;
     for (int i=; i<=bcnt; i++) if (dis[i]>ret) ret=dis[i];
     return ret+val[S];
 }
 void find(int n)
 {
    memset(dfn,,sizeof(dfn));
    memset(instack,,sizeof(instack));
    memset(val,,sizeof(val));
    memset(low,,sizeof(low));
    bcnt=depth=;
    for(int i =  ; i < n ; i++)
    if (!dfn[i]) tarjan(i);
 }
 int main()
 {
     int cas;
     scanf("%d",&cas);
     while (cas--)
     {
         scanf("%d%d",&n,&m);
         for (int i=; i<n; i++)
         {
             getchar();
             for (int j=; j<m; j++) c[i][j]=getchar();
         }
         init();
         int x,y;
         for (int i=; i<n; i++)
           for (int j=; j<m; j++)
           {
               int u= i*m+j;
               if (c[i][j]=='*')
               {
                   w[u]=;
                   scanf("%d%d",&x,&y);
                   addedge(u,x*m+y);
               }
               else w[u]=c[i][j]-'';
               if (c[i][j]=='#') { w[u]=; continue; }
               if (i!=n- && c[i+][j]!='#') addedge(u,u+m);
               if (j!=m- && c[i][j+]!='#') addedge(u,u+);
           }
         find(n*m);
         int u,v;
         for (int i=; i<t; i++)
         {
             u=edge[i].u; v=edge[i].v;
             if (belong[u]!=belong[v]) adj[belong[u]].push_back(belong[v]);
         }
         printf("%d\n",lpfa(belong[]));
     }
     return ;
 }