BZOJ 4823 老C的方块

把格子分成四类 第一类是蓝线左右的相邻两个格子 第二类为与蓝线左边格子相邻的点 第三类为与蓝线右边格子相邻的点

建边就S朝第二类每个点建边 第二类每个点朝其相邻的第一类建边 第一类从左格子朝右格子建边 第一类朝与其相邻的第三类建边 第三类朝T建边

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef int JQK;
const int dir[][] = { , -, -, , , , ,  };
struct node {
        int x, y, w, color;
} p[];
int n, m;
map<pair<int, int>, int> mp;
namespace dinic {
        const int MAXN = ;
        const int MAXM = ;
        const int INF = ;
        int Head[MAXN], cur[MAXN], lev[MAXN], to[MAXM << ], nxt[MAXM << ], ed = ;
        int S, T, MAXP;
        JQK f[MAXM << ];
        inline void addedge(int u, int v, JQK cap) {
                to[++ed] = v;
                nxt[ed] = Head[u];
                Head[u] = ed;
                f[ed] = cap;
                to[++ed] = u;
                nxt[ed] = Head[v];
                Head[v] = ed;
                f[ed] = ;
                return;
        }
        inline bool BFS() {
                int u;
                for (int i = ; i <= MAXP + ; i++) {
                        lev[i] = -;
                }
                //memset(lev, -1, sizeof(lev));
                queue<int>q;
                lev[S] = ;
                q.push(S);
                while (q.size()) {
                        u = q.front();
                        q.pop();
                        for (int i = Head[u]; i; i = nxt[i])
                                if (f[i] && lev[to[i]] == -) {
                                        lev[to[i]] = lev[u] + ;
                                        q.push(to[i]);
                                        /*
                                        if (to[i] == T)
                                        {
                                                return 1;
                                        }
                                        magic one way optimize
                                        */
                                }
                }
                for (int i = ; i <= MAXP + ; i++) {
                        cur[i] = Head[i];
                }
                //memcpy(cur, Head, sizeof Head);
                return lev[T] != -;
        }
        inline JQK DFS(int u, JQK maxf) {
                if (u == T || !maxf) {
                        return maxf;
                }
                JQK cnt = , tem;
                for (int &i = cur[u]; i; i = nxt[i])
                        if (f[i] && lev[to[i]] == lev[u] + ) {
                                tem = DFS(to[i], min(maxf, f[i]));
                                maxf -= tem;
                                f[i] -= tem;
                                f[i ^ ] += tem;
                                cnt += tem;
                                if (!maxf) {
                                        break;
                                }
                        }
                if (!cnt) {
                        lev[u] = -;
                }
                return cnt;
        }
        JQK Dinic() {
                JQK ans = ;
                while (BFS()) {
                        ans += DFS(S, INF);
                }
                return ans;
        }
        void init(int SS, int TT) {
                for (int i = ; i <= MAXP + ; i++) {
                        Head[i] = ;
                }
                ed = ;
                S = SS;
                T = TT;
                return;
        }
        void work() {
                for (int i = ; i <= n; i++) {
                        if (p[i].color == ) {
                                addedge(i, T, p[i].w);
                        } else if (p[i].color == ) {
                                addedge(S, i, p[i].w);
                        } else if (p[i].color == ) {
                                for (int j = ; j < ; j++) {
                                        int dx = p[i].x + dir[j][];
                                        int dy = p[i].y + dir[j][];
                                        int aim = mp[make_pair(dx, dy)];
                                        if (aim == ) {
                                                continue;
                                        } else if (p[aim].color == ) {
                                                addedge(aim, i, INF);
                                        } else if (p[aim].color == ) {
                                                addedge(i, aim, min(p[aim].w, p[i].w));
                                        }
                                }
                        } else {
                                for (int j = ; j < ; j++) {
                                        int dx = p[i].x + dir[j][];
                                        int dy = p[i].y + dir[j][];
                                        int aim = mp[make_pair(dx, dy)];
                                        if (aim == ) {
                                                continue;
                                        } else if (p[aim].color == ) {
                                                addedge(i, aim, INF);
                                        }
                                }
                        }
                }
                printf("%d\n", Dinic());
        }
}
int get_color(int x, int y) {
        if (x & ) {
                return y %  ==  || y %  == ;
        } else {
                return y %  ==  || y %  == ;
        }
}
int main() {
        int r, c;
        int s, t;
        int x, y, w;
        while (scanf("%d %d %d", &c, &r, &n) == ) {
                mp.clear();
                for (int i = ; i <= n; i++) {
                        scanf("%d %d %d", &y, &x, &w);
                        p[i].x = x, p[i].y = y, p[i].w = w;
                        mp[make_pair(x, y)] = i;
                        if ((x + y + ) & ) {
                                p[i].color = get_color(x, y) ?  : ;
                        } else {
                                p[i].color = get_color(x, y) ?  : ;
                        }
                        //cout << p[i].color << endl;
                }
                dinic::MAXP = n + ;
                dinic::init(n + , n + );
                dinic::work();
        }
        return ;
}