bzoj3144

由於本蒟蒻看不懂題目。。。。所以只是知道了個#include<set>
#include<map>
#include<cmath>
#include<ctime>
#include<queue>
#include<cstdio>
#include<vector>
#include<cstring>
#include<cstdlib>
#include<iostream>
#include<algorithm>
#define rad 100000000
#define inf 1000000000
#define ll long long 
#define eps 1e-10
#define pa pair<ll,int>
using namespace std;
ll read()
{
    ll x=0,f=1;char ch=getchar();
    while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
    while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
    return x*f;
}
int xx[4]={0,0,1,-1},yy[4]={1,-1,0,0};
int P,Q,r,d,T,cnt=1;
int f[45][45][45];
int cur[100005],last[100005],h[100005],q[100005];
struct edge{
int to,next,v;
}e[1000005];
int p(int x,int y,int z)
{
if(z==0)return 0;
return (z-1)*P*Q+(x-1)*Q+y;
}
void insert(int u,int v,int w)
{
e[++cnt].to=v;e[cnt].next=last[u];last[u]=cnt;e[cnt].v=w;
e[++cnt].to=u;e[cnt].next=last[v];last[v]=cnt;e[cnt].v=0;
}
void build()
{
for(int i=1;i<=P;i++)
for(int j=1;j<=Q;j++)
{
for(int k=1;k<=r;k++)
{
insert(p(i,j,k-1),p(i,j,k),f[i][j][k]);
if(k>d)
for(int dir=0;dir<4;dir++)
{
int nx=i+xx[dir],ny=j+yy[dir];
if(nx<1||ny<1||nx>P||ny>Q)continue;
insert(p(i,j,k),p(nx,ny,k-d),inf);
}
}
insert(p(i,j,r),T,inf);
}
}
bool bfs()
{
int head=0,tail=1;
memset(h,-1,sizeof(h));
q[0]=0;h[0]=0;
while(head!=tail)
{
int now=q[head];head++;
for(int i=last[now];i;i=e[i].next)
if(h[e[i].to]==-1&&e[i].v)
{
h[e[i].to]=h[now]+1;
q[tail++]=e[i].to;
}
}
return h[T]!=-1;
}
int dfs(int x,int f)
{
if(x==T)return f;
int w,used=0;
for(int i=cur[x];i;i=e[i].next)
if(h[x]+1==h[e[i].to])
{
w=dfs(e[i].to,min(f-used,e[i].v));
used+=w;e[i].v-=w;e[i^1].v+=w;
if(e[i].v)cur[x]=i;
if(used==f)return f;
}
if(!used)h[x]=-1;
return used;
}
int dinic()
{
int tmp=0;
while(bfs())
{
for(int i=0;i<=T;i++)cur[i]=last[i];
tmp+=dfs(0,inf);
}
return tmp;
}
int main()
{
P=read();Q=read();r=read();T=P*Q*r+1;
d=read();
for(int i=1;i<=r;i++)
for(int j=1;j<=P;j++)
for(int k=1;k<=Q;k++)
f[j][k][i]=read();
build();
printf("%d\n",dinic());
return 0;
} 思路看黃學長博