bzoj2132: 圈地计划

要分成两坨对吧。。 所以显然最小割

但是不兹辞啊。。

最小割是最小的啊 求最大费用怎么玩啊

那咱们就把所有费用都加起来，减掉一个最小的呗

但是两个属于不同集合的点贡献的价值是负的啊

网络流怎么跑负的啊

那咱就交换一下呗

原图是二分图啊，把另一部分与S和T连边的流量换一下就好啦。

注意哦 n和m可能为1 所以累加C的时候写成ans += C[i][j] * (4 - (i == 1 || i == n) - (j == 1 || j == m));就错啦。

要么在加边的时候累加，要么写成ans += C[i][j] * ((i != 1) + (i != n) + (j != 1) + (j != m)); 

#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<algorithm>
#include<iostream>
#define rep(i, a, b) for(int i = (a), _end = (b); i <= _end; ++i)

using namespace std;

void setIO(const string& s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}
template<typename Q> Q read(Q& x) {
    static char c, f;
    for(f = 0; c = getchar(), !isdigit(c); ) if(c == '-') f = 1;
    for(x = 0; isdigit(c); c = getchar()) x = x * 10 + c - '0';
    if(f) x = -x;
    return x;
}
template<typename Q> Q read() {
    static Q x; read(x); return x;
}

// ISAP
const int N = 100 * 100 + 10, M = 100 * 100 * 4 + 10, INF = ~0u >> 1;

struct Edge {
    int to, adv;
    Edge *next;
    Edge(int to = 0, int adv = 0, Edge *next = 0) : to(to), adv(adv), next(next) {}
}pool[M * 2], *pis = pool, *fir[N], *pre[N];

void AddEdge(int u, int v, int w, int b = 0) {
    fir[u] = new(pis++) Edge(v, w, fir[u]);
    fir[v] = new(pis++) Edge(u, w * b, fir[v]);
}

Edge *inv(Edge *p) {
    return pool + ((p - pool) ^ 1);
}

int d[N], q[N], ql, qr;

namespace ISAP {
    int n, s, t;
    int num[N];
    Edge *cur[N];
    
    void insert(int u, int dis) {
        if(d[u] == n) {
            d[u] = dis;
            q[qr++] = u;
        }
    }
    
    void BFS() {
        for(int u = 1; u <= n; u++) {
            d[u] = n;
        }
        ql = qr = 0;
        insert(t, 0);
        while(ql ^ qr) {
            int u = q[ql++];
            for(Edge *p = fir[u]; p; p = p->next) if(inv(p)->adv){
                insert(p->to, d[u] + 1);
            }
        }
    }
    
    int Augment() {
        int a = INF;
        for(int u = t; u != s; u = inv(pre[u])->to) {
            a = min(a, pre[u]->adv);
        }
        for(int u = t; u != s; u = inv(pre[u])->to) {
            pre[u]->adv -= a;
            inv(pre[u])->adv += a;
        }
        return a;
    }
    
    int Maxflow() {
        memset(num, 0, sizeof num);
        BFS();
        for(int u = 1; u <= n; u++) {
            cur[u] = fir[u];
            num[d[u]]++;
        }
        for(int i = 1; i < d[s]; i++) {
            if(!num[i]) return 0;
        }
        int flow = 0;
        for(int u = s; d[s] < n; ) {
            if(u == t) {
                flow += Augment();
                u = s;
            }
            int ok = 0;
            for(Edge *&p = cur[u]; p; p = p->next) if(p->adv) {
                int v = p->to;
                if(d[v] + 1 == d[u]) {
                    pre[u = v] = p;
                    ok = 1;
                    break;
                }
            }
            if(!ok) {
                int &dis = d[u];
                if(!--num[dis]) break;
                dis = n;
                for(Edge *p = (cur[u] = fir[u]); p; p = p->next) if(p->adv) {
                    dis = min(dis, d[p->to] + 1);
                }
                num[dis]++;
                if(u != s) u = inv(pre[u])->to;
            }
        }
        return flow;
    }
    
    int main(int _n, int _s, int _t) {
        n = _n, s = _s, t = _t;
        return Maxflow();
    }
}

int n, m;

int encode(int x, int y) {
    return (x - 1) * m + y;
}

const int maxn = 100 + 10;

int A[maxn][maxn], B[maxn][maxn], C[maxn][maxn];

int main() {
#ifdef DEBUG
    freopen("in.txt", "r", stdin);
    freopen("out.txt", "w", stdout);
#endif
    
    read(n), read(m);
    int ans = 0;
    rep(i, 1, n) rep(j, 1, m) ans += read(A[i][j]);
    rep(i, 1, n) rep(j, 1, m) ans += read(B[i][j]);
    rep(i, 1, n) rep(j, 1, m) read(C[i][j]);
    int s = n * m + 1, t = s + 1;
    rep(i, 1, n) rep(j, 1, m) {
        int u = encode(i, j);
        if((i ^ j) & 1) swap(A[i][j], B[i][j]);
        AddEdge(s, u, A[i][j]);
        AddEdge(u, t, B[i][j]);
        if(i < n) AddEdge(u, encode(i + 1, j), C[i][j] + C[i+1][j], 1), ans += C[i][j] + C[i+1][j];
        if(j < m) AddEdge(u, encode(i, j + 1), C[i][j] + C[i][j+1], 1), ans += C[i][j] + C[i][j+1];
    }
    
    printf("%d
", ans - ISAP::main(t, s, t));
    
    return 0;
}