1 2 3
1
4 1 

3 4 

1 4 

out:3
ans:4

给组hack，可以有人帮忙调一下吗，感觉找不到问题。

#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N=2e5+5,inf=1e18;
int idx=1,e[N],w[N],ne[N],h[N],dep[N],s,t,q,p,r,now[N],dis[42][42][42];


inline int read(){
    int a=1,b=0;
    char ch=getchar();
    while(ch<'0'||ch>'9'){
        if(ch=='-') a=-a;
        ch=getchar();
    }
    while(ch>='0'&&ch<='9'){
        b=(b<<1)+(b<<3)+(ch^48);
        ch=getchar();
    }
    return a*b;
}

inline int lock(int a,int b,int c){
    return a*41*41+b*41+c;
}


inline void add(int a,int b,int c){
    // cout<<a/(41*41)<<" "<<a/41%41<<" "<<a%41<<endl;
    // cout<<b/(41*41)<<" "<<b/41%41<<" "<<b%41<<endl;
    // cout<<c<<endl;
    // puts("");
    // cout<<a<<" "<<b<<" "<<c<<endl;
    e[++idx]=b;
    w[idx]=c;
    ne[idx]=h[a];
    h[a]=idx;
    e[++idx]=a;
    w[idx]=0;
    ne[idx]=h[b];
    h[b]=idx;
}

// inline bool bfs(){
    
// }
inline int bfs(){
    queue<int>q;
    for(int i=0;i<=lock(41,41,41);i++){
        dep[i]=inf;
    }
    q.push(s);
    dep[s]=0;
    now[s]=h[s];
    while(!q.empty()){
        int u=q.front();
        q.pop();
        for(int i=h[u];i;i=ne[i]){
            int v=e[i];
            if(w[i]&&dep[v]==inf){
                now[v]=h[v];
                dep[v]=dep[u]+1;
                q.push(v);
                if(v==t) return 1;
            }
        }
    }
    return 0;
}
inline int dfs(int u,int flow){
    if(u==t) return flow;
    int res=0,k;
    for(int i=now[u];i;i=ne[i]){
        int v=e[i];
        now[u]=i;
        if(w[i]&&dep[v]==dep[u]+1){
            k=dfs(v,min(flow,w[i]));
            if(!k) dep[v]=inf;
            w[i]-=k;
            w[i^1]-=k;
            res+=k;
            flow-=k;
        }
    }
    return res;
}


signed main(){
    p=read(),q=read(),r=read();//r层p行q列
    s=0,t=lock(41,41,41);
    int d=read();
    for(int i=1;i<=r;i++){
        for(int j=1;j<=p;j++){
            for(int k=1;k<=q;k++){
                dis[i][j][k]=read();//i层j行k列
            }
        }
    }
    for(int i=1;i<=p;i++){
        for(int j=1;j<=q;j++){
            add(0,lock(1,i,j),dis[1][i][j]);
            add(lock(r,i,j),t,1e18);
            // e[0][0][0].push_back({{1,i,j},dis[1][j][k]});
            // e[r][i][j].push_back({{r+1,i,j},1e18});
        }
    }
    for(int i=1;i<r;i++){
        for(int j=1;j<=p;j++){
            for(int k=1;k<=q;k++){
                add(lock(i,j,k),lock(i+1,j,k),dis[i+1][j][k]);
            }
        }
    }
    for(int i=d+1;i<=r;i++){
        for(int j=1;j<=p;j++){
            for(int k=1;k<=q;k++){
                if(j!=1) add(lock(i,j,k),lock(i-d,j-1,k),dis[i-d][j-1][k]);
                if(j!=p) add(lock(i,j,k),lock(i-d,j+1,k),dis[i-d][j+1][k]);
                if(k!=1) add(lock(i,j,k),lock(i-d,j,k-1),dis[i-d][j][k-1]);
                if(k!=q) add(lock(i,j,k),lock(i-d,j,k+1),dis[i-d][j][k+1]);
            }
        }
    }
    int ans=0;
    while(bfs()){
        ans+=dfs(s,inf);
    }
    cout<<ans<<endl;
    return 0;
}