bzoj 3144

3144

思路：

　　xxy；

代码：

#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;
#define maxn 64005
#define INF 0x3f3f3f3f
const int dx[]={,-,,,};
const int dy[]={,,,,-};
int deep[maxn],head[maxn],E[maxn<<],V[maxn<<],F[maxn<<],ans;
int n,m,r,d,ai[][][],id[][][],s,t,cnt,que[maxn];
inline void in(int &now)
{
    char Cget=getchar();now=;
    while(Cget>''||Cget<'') Cget=getchar();
    while(Cget>=''&&Cget<='')
    {
        now=now*+Cget-'';
        Cget=getchar();
    }
}
inline void edge_add(int u,int v,int f)
{
    E[++cnt]=head[u],V[cnt]=v,F[cnt]=f,head[u]=cnt;
    E[++cnt]=head[v],V[cnt]=u,F[cnt]=,head[v]=cnt;
}
bool bfs()
{
    for(int i=s;i<=t;i++) deep[i]=-;
    deep[s]=,que[]=s;int h=,tail=,now;
    while(h<tail)
    {
        now=que[h++];
        for(int i=head[now];i;i=E[i])
            if(F[i]&&deep[V[i]]<)
            {
                deep[V[i]]=deep[now]+;
                if(V[i]==t) return true;
                que[tail++]=V[i];
            }
    }
    return false;
}
int flowing(int now,int flow)
{
    if(now==t||flow<=) return flow;
    int oldflow=,pos;
    for(int i=head[now];i;i=E[i])
    {
        if(deep[V[i]]!=deep[now]+||!F[i]) continue;
        pos=flowing(V[i],min(flow,F[i]));
        F[i]-=pos,F[i^]+=pos,flow-=pos,oldflow+=pos;
        if(!flow) return oldflow;
    }
    if(!oldflow) deep[now]=-;
    return oldflow;
}
int main()
{
    in(n),in(m),in(r),in(d);
    for(int i=;i<=r;i++)
        for(int v=;v<=n;v++)
            for(int e=;e<=m;e++) in(ai[i][v][e]),id[i][v][e]=++cnt;
    s=,t=cnt+,cnt=;
    for(int i=;i<=n;i++)
        for(int v=;v<=m;v++)
            edge_add(s,id[][i][v],ai[][i][v]),edge_add(id[r][i][v],t,INF);
    for(int z=;z<=r;z++)
    {
        for(int i=;i<=n;i++)
            for(int v=;v<=m;v++) edge_add(id[z-][i][v],id[z][i][v],ai[z][i][v]);
        if(z>d)
        {
            for(int i=;i<=n;i++)
                for(int v=;v<=m;v++)
                    for(int e=;e<=;e++)
                        if(i+dx[e]>&&i+dx[e]<=n&&v+dy[e]>&&v+dy[e]<=m)
                            edge_add(id[z][i][v],id[z-d][i+dx[e]][v+dy[e]],INF);
        }
    }
    while(bfs()) ans+=flowing(s,INF);
    printf("%d\n",ans);
    return ;
}