\nhttp:\/\/www.lydsy.com\/JudgeOnline\/problem.php?id=1340<\/p>\n
\r\n\r\nconst int N = 1009, M = int(4e6) + 9;\r\n\r\n\/\/struct Network_Flow{\r\n\r\nint D[N], hd[N], suc[M], to[M], cap[M];\r\nint n, m, s, t;\r\n\r\ninline void ae(int x, int y, int c){\r\n suc[m] = hd[x], hd[x] = m, to[m] = y, cap[m++] = c,\r\n suc[m] = hd[y], hd[y] = m, to[m] = x, cap[m++] = 0;\r\n}\r\n\r\ninline void aee(int x, int y, int c){\r\n suc[m] = hd[x], hd[x] = m, to[m] = y, cap[m++] = c,\r\n suc[m] = hd[y], hd[y] = m, to[m] = x, cap[m++] = c;\r\n}\r\n\r\n#define v to[i]\r\n#define c cap[i]\r\n#define f cap[i^1]\r\n\r\nLL sap(){\r\n LL z=0; static int cnt[N],cur[N],pre[N];\r\n fill(D,D+n,n),fill(cnt,cnt+n,0);cnt[n]=n;\r\n int u=s;cur[s]=hd[s];while (D[s]){\r\n#define i cur[u]\r\n if (u==t){\r\n int d=INF;for(u=s;u!=t;u=v)checkMin(d,c);\r\n z+=d;for(u=s;u!=t;u=v)f+=d,c-=d;u=s;\r\n }\r\n#undef i\r\n int i;for(i=cur[u];i;i=suc[i]){\r\n if(D[u]+1==D[v]&&c){cur[u]=i,cur[v]=hd[v],pre[v]=u,u=v;break;}\r\n }\r\n if (!i){\r\n if (!--cnt[D[u]])break;\r\n D[u]=1;REP_G(i,u)if(c)checkMax(D[u],D[v]);--D[u];\r\n ++cnt[D[u]];if(u==s)cur[u]=hd[u];else u=pre[u];\r\n }\r\n }\r\n\r\n return z;\r\n}\r\n#undef f\r\n#undef c\r\n#undef v\r\n\/\/} G;\r\n\r\nint L, W;\r\nint xx[N], yy[N];\r\n\r\nvoid init(){\r\n\r\n RD(L, W); RD(n);\r\n REP_1(i, n) RD(xx[i], yy[i]);\r\n\r\n s = 0, t = 2*n + 1, m = 2;\r\n\r\n REP_1(i, n){\r\n ae(2*i-1,2*i,1);\r\n if (yy[i] <= 100) ae(s, 2*i-1, INF);\r\n if (yy[i] >= W - 100) ae(2*i, t, INF);\r\n FOR_1(j, i+1, n) if (sqr(xx[i]-xx[j]) + sqr(yy[i]-yy[j]) <= sqr(200)){\r\n ae(2*i, 2*j-1, INF);\r\n ae(2*j, 2*i-1, INF);\r\n }\r\n }\r\n\r\n n = t + 1;\r\n}\r\n\r\nint main(){\r\n\r\n#ifndef ONLINE_JUDGE\r\n freopen("in.txt", "r", stdin);\r\n\r\n#endif\r\n\r\n init(); OT(sap());\r\n}\r\n<\/pre>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","enabled":false}}},"categories":[22],"tags":[],"class_list":["post-1182","post","type-post","status-publish","format-standard","hentry","category-bzoj"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p2tdP7-j4","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts\/1182","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/comments?post=1182"}],"version-history":[{"count":1,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts\/1182\/revisions"}],"predecessor-version":[{"id":1185,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts\/1182\/revisions\/1185"}],"wp:attachment":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/media?parent=1182"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/categories?post=1182"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/tags?post=1182"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}