#include<stdio.h>#include<string.h>#include<algorithm>#include<queue>using namespace std;#define maxn 5010#define maxm 10030#define inf 1000000000int min(int a, int b){ return a < b ? a : b;}struct E{ int u, v, c, w, next;}edge[maxm<<3];int head[maxn], tot;int n, m, k;int S, T;void init(){ tot = 0; memset(head, -1, sizeof(head));}void add(int s, int t, int c, int w){ edge[tot].u = s; edge[tot].v = t; edge[tot].c = c; edge[tot].w = w; edge[tot].next = head[s]; head[s] = tot++; edge[tot].u = t; edge[tot].v = s; edge[tot].c = 0; edge[tot].w = -w; edge[tot].next = head[t]; head[t] = tot++;}bool vis[maxn];int pre[maxn];int dis[maxn];bool spfa(int s, int t, int n){ int i, u, v; for(i = 0; i <= n; i++) vis[i] = 0, pre[i] = -1, dis[i] = -inf; queue<int> q; q.push(s); vis[s] = 1; dis[s] = 0; while(!q.empty()) { u = q.front(); q.pop(); vis[u] = 0; for(i = head[u]; i != -1; i = edge[i].next) { v = edge[i].v; if(edge[i].c && dis[v] < dis[u] + edge[i].w) { dis[v] = dis[u] + edge[i].w; pre[v] = i; if(!vis[v]) { vis[v] = 1; q.push(v); } } } } if(dis[t] == -inf) return 0; return 1;}int mfmw(int s, int t, int n) { int i, maxf = 0, minw = 0, aug; while(spfa(s, t, n)) { aug = inf; for(i = pre[t]; i != -1; i = pre[edge[i].u]) aug = min(aug, edge[i].c); for(i = pre[t]; i != -1; i = pre[edge[i].u]) { edge[i].c -= aug; edge[i^1].c += aug; } maxf += aug; minw += dis[t] * aug; } return minw;}int main(){ int i, j; int x, y, z; while( ~scanf("%d%d", &n, &k)) { init(); S = 0; T = 2*n*n+1; add(S, 1, k, 0); add(n*n*2, T, k, 0); for(i = 1; i <= n; i++) for(j = 1; j <= n; j++) { scanf("%d", &z); x = (i-1)*n+j; add(x, x+n*n, 1, z); add(x, x+n*n, inf, 0); if(i < n) add(x+n*n, x+n, inf, 0); if(j < n) add(x+n*n, x+1, inf, 0); } printf("%d\n", mfmw(S, T, T+1)); } return 0;}
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