1 #include <cstdio> 2 #include <cstring> 3 #include <algorithm> 4 #include <iostream> 5 #include <queue> 6 using namespace std; 7 #define N 1000010 8 #define INF 0x3f3f3f3f 9 struct Edge {10     int v, cap, nxt;11 } edge[N*6];12 int head[N], cur[N], pre[N], tot, gap[N], dis[N], S, T;13 14 void Add(int u, int v, int cap) {15     edge[tot] = (Edge) {v, cap, head[u]}; head[u] = tot++;16     edge[tot] = (Edge) {u, cap, head[v]}; head[v] = tot++;17 }18 19 int BFS() {20     memset(gap, 0, sizeof(gap));21     memset(dis, INF, sizeof(dis));22     queue<int> que;23     que.push(T);24     dis[T] = 0; gap[0] = 1;25     while(!que.empty()) {26         int u = que.front(); que.pop();27         for(int i = head[u]; ~i; i = edge[i].nxt) {28             int v = edge[i].v;29             if(INF != dis[v]) continue;30             dis[v] = dis[u] + 1;31             gap[dis[v]]++;32             que.push(v);33         }34     }35 }36 37 int ISAP(int n) {38     BFS();39     memcpy(cur, head, sizeof(cur));40     int flow, ans = 0, u = pre[S] = S, i, index;41     while(dis[S] < n) {42         if(u == T) {43             flow = INF;44             for(i = S; i != T; i = edge[cur[i]].v)45                 if(flow > edge[cur[i]].cap) flow = edge[cur[i]].cap, index = i;46             for(i = S; i != T; i = edge[cur[i]].v)47                 edge[cur[i]].cap -= flow, edge[cur[i]^1].cap += flow;48             ans += flow; u = index;49         }50         for(i = cur[u]; ~i; i = edge[i].nxt) if(edge[i].cap > 0 && dis[edge[i].v] == dis[u] - 1) break;51         if(~i) {52             cur[u] = i; pre[edge[i].v] = u; u = edge[i].v;53         } else {54             if(--gap[dis[u]] == 0) break;55             int md = n + 1;56             for(i = head[u]; ~i; i = edge[i].nxt)57                 if(edge[i].cap > 0 && dis[edge[i].v] < md) md = dis[edge[i].v], cur[u] = i;58             gap[dis[u] = md + 1]++;59             u = pre[u];60         }61     }62     return ans;63 }64 65 int main() {66     int n, m, w;67     scanf("%d%d", &n, &m);68     memset(head, -1, sizeof(head));69     tot = 0;70     for(int i = 0; i < n; i++)71         for(int j = 2; j <= m; j++)72             scanf("%d", &w), Add(j - 1 + i * m, j + i * m, w);73     for(int i = 1; i < n; i++)74         for(int j = 1; j <= m; j++)75             scanf("%d", &w), Add(j + (i - 1) * m, j + i * m, w);76     for(int i = 1; i < n; i++)77         for(int j = 2; j <= m; j++)78             scanf("%d", &w), Add(j - 1 + (i - 1) * m, j + i * m, w);79     S = 1, T = n * m;80     printf("%d\n", ISAP(T + 1));81     return 0;82 }