[bzoj1001]狼抓兔子

#include<cstdio>
#include<cstring>
#define inf 0x3f3f3f3f
#define r register
#define min(a,b) (a<b?a:b) 
typedef long long ll;
inline int read(){
    r int x=0,f=1;r char c=getchar();
    for(;c<‘0‘||c>‘9‘;f=c==‘-‘?-1:1,c=getchar());
    for(;c>=‘0‘&&c<=‘9‘;x=(x<<3)+(x<<1)+c-‘0‘,c=getchar());
    return x*f;
}
struct AriM{int to,nxt,c;}e[2996005*2];
int cnt,head[1000005];
int h[1000005],q[1500005];
inline void ins(int s,int t,int c){
    e[++cnt].to=t,e[cnt].nxt=head[s],head[s]=cnt,e[cnt].c=c;
    e[++cnt].to=s,e[cnt].nxt=head[t],head[t]=cnt,e[cnt].c=c;
}
int n,m,ans;
bool bfs(){
    memset(h,-1,sizeof(h));
    r int s=0,t=1;
    q[s]=1;h[1]=0;
    while(s<t){   
        r int v=q[s++];
        for(r int i=head[v];i;i=e[i].nxt)
            if(e[i].c&&h[e[i].to]<0){
                q[t++]=e[i].to;
                h[e[i].to]=h[v]+1;                 
            }
    }
    return h[n*m]!=-1;
}
int dfs(int v,int f){
    if(v==n*m)return f;
    r int used=0;
    for(r int i=head[v];i;i=e[i].nxt)
        if(e[i].c&&h[e[i].to]==h[v]+1){
            r int w=f-used;
            w=dfs(e[i].to,min(w,e[i].c));
            e[i].c-=w;e[i+1].c+=w;used+=w;
            if(used==f)return f;
        }
    if(!used)h[v]=-1;
    return used;
}
void Dinic(){while(bfs())ans+=dfs(1,inf);}
int main(){
    n=read();m=read();
    for(r int i=1;i<=n;i++)
        for(r int j=1;j<m;j++)
            ins(i*m-m+j,i*m-m+j+1,read());
    for(r int i=1;i<n;i++)
        for(r int j=1;j<=m;j++)
            ins(i*m-m+j,i*m+j,read());
    for(r int i=1;i<n;i++)
        for(r int j=1;j<m;j++)
            ins(i*m-m+j,i*m+j+1,read());
    Dinic();
    printf("%d\n",ans);
    return 0;
}