POJ 2112 Optimal Milking(最大流+二分)

题目链接

测试dinic模版，不知道这个模版到底对不对，那个题用这份dinic就是过不了。加上优化就WA，不加优化TLE。

 #include <cstdio>
 #include <string>
 #include <cstring>
 #include <queue>
 #include <map>
 #include <algorithm>
 using namespace std;
 #define INF 0x3ffffff
 struct node
 {
     int u,v,next,re,w;
 } edge[];
 int first[],dis[];
 int p[][];
 int t;
 int sv,ev,K,C,M;
 void CL()
 {
     t = ;
     memset(first,-,sizeof(first));
 }
 void add(int u,int v,int w)
 {
     edge[t].u = u;
     edge[t].v = v;
     edge[t].w = w;
     edge[t].re = t+;
     edge[t].next = first[u];
     first[u] = t++;
     edge[t].u = v;
     edge[t].v = u;
     edge[t].w = ;
     edge[t].re = t-;
     edge[t].next = first[v];
     first[v] = t ++;
 }
 int bfs()
 {
     int u,v,i;
     memset(dis,0xff,sizeof(dis));
     queue<int> que;
     que.push(sv);
     dis[sv] = ;
     while(!que.empty())
     {
         u = que.front();
         que.pop();
         for(i = first[u]; i != -; i = edge[i].next)
         {
             v = edge[i].v;
             if(edge[i].w > &&dis[v] < )
             {
                 dis[v] = dis[u] + ;
                 que.push(v);
             }
         }
     }
     if(dis[ev] > ) return ;
     else return ;
 }
 int dfs(int u,int step)
 {
     int i,a = ,v,flag = ;
     if (u == ev) return step;
     for (i = first[u];i != -&&flag < step; i = edge[i].next)//flag<step
     {
         v = edge[i].v;
         if (edge[i].w > && dis[v] == dis[u]+&&(a = dfs(v,min(step,edge[i].w))))
         {
             edge[i].w -= a;
             flag += a;//这里
             edge[edge[i].re].w += a;
             return a;
         }
     }
     if(flag == ) dis[u] = -;//这里
     return flag;
 }
 void build(int x)
 {
     int i,j;
     CL();
     for(i = ; i <= K; i ++)
     {
         add(,i,M);
     }
     for(i = ; i <= K; i ++)
     {
         for(j = ; j <= C; j ++)
         {
             if(p[i][j+K] <= x)
             add(i,K+j,);
         }
     }
     for(i = ;i <= C;i ++)
     {
         add(i+K,ev,);
     }
 }
 int fun(int x)
 {
     int ans = ,res;
     build(x);
     while(bfs())
     {
           while(res=dfs(sv,INF))
           ans += res;
     }
     if(ans == C)
         return ;
     else
         return ;
 }
 int bin(int l,int r)
 {
     int str,mid,end;
     str = l;
     end = r;
     while(str < end)
     {
         mid = (str + end)/;
         if(fun(mid))
         {
             end = mid;
         }
         else
         {
            str = mid + ;
         }
     }
     return end;
 }
 int main()
 {
     int i,j,k;
     while(scanf("%d%d%d",&K,&C,&M)!=EOF)
     {
         for(i = ;i <= K+C;i ++)
         {
             for(j = ;j <= K+C;j ++)
             {
                 scanf("%d",&p[i][j]);
                 if(i != j&&p[i][j] == )
                 p[i][j] = INF;
             }
         }
         for(i = ;i <= K+C;i ++)
         {
             for(j = ;j <= K+C;j ++)
             {
                 for(k = ;k <= K+C;k ++)
                 {
                     if(p[j][k] > p[j][i] + p[i][k])
                     p[j][k] = p[j][i] + p[i][k];
                 }
             }
         }
         sv = ;
         ev = K+C+;
         int maxz = ;
         for(i = ;i <= K+C;i ++)
         {
             for(j = ;j <= K+C;j ++)
             maxz = max(maxz,p[i][j]);
         }
         printf("%d\n",bin(,maxz));
     }
     return ;
 }