POJ 1724 ROADS(二维SPFA）

题目链接

用STL实现超时了，用普通队列500+，看到spfa，反应太迟钝了。

 #include <cstring>
 #include <cstdio>
 #include <string>
 #include <iostream>
 #include <algorithm>
 #include <vector>
 #include <queue>
 using namespace std;
 #define INF 0x7fffffff
 int d[][];
 int first[];
 bool in[][];
 int q1[];
 int q2[];
 int t,k,n;
 struct node
 {
     int u,v,w,next,c;
 }edge[];
 void CL()
 {
     t = ;
     memset(first,-,sizeof(first));
 }
 void add(int u,int v,int w,int c)
 {
     edge[t].u = u;
     edge[t].v = v;
     edge[t].w = w;
     edge[t].c = c;
     edge[t].next = first[u];
     first[u] = t ++;
 }
 int spfa(int str,int end)
 {
     int x,y,v,i,j,ans,l,r;

     for(i = ;i <= end;i ++)
     {
         for(j = ;j <= k;j ++)
         {
             in[i][j] = ;
             d[i][j] = INF;
         }
     }
     l = r = ;
     q1[] = str;
     q2[] = ;
     in[str][] = ;
     d[str][] = ;
     while(l <= r)
     {
         x = q1[l];
         y = q2[l];
         l ++;
         in[x][y] = ;
         for(i = first[x];i != -;i = edge[i].next)
         {
             v = edge[i].v;
             if(y + edge[i].c <= k)
             {
                 if(d[v][y+edge[i].c] > d[x][y] + edge[i].w)
                 {
                     d[v][y+edge[i].c] = d[x][y] + edge[i].w;
                     if(!in[v][y+edge[i].c])
                     {
                         r ++;
                         q1[r] = v;
                         q2[r] = y+edge[i].c;
                         in[v][y+edge[i].c] = ;
                     }
                 }
             }
         }
     }
     ans = INF;
     for(i = ;i <= k;i ++)
     {
         ans = min(ans,d[end][i]);
     }
     return ans;
 }
 int main()
 {
     int m,sv,ev,w,c,ans,i;
     scanf("%d%d%d",&k,&n,&m);
     CL();
     for(i = ;i <= m;i ++)
     {
         scanf("%d%d%d%d",&sv,&ev,&w,&c);
         add(sv,ev,w,c);
     }
     ans = spfa(,n);
     if(ans == INF)
     printf("-1\n");
     else
     printf("%d\n",ans);
     return ;
 }