\n
4.00<\/span><\/p>\n\u8f93\u51fa\u8bf4\u660e:<\/p>\n
FJ\u9009\u62e9\u5728\u519c\u573a1\u548c\u519c\u573a2\u95f4\u5efa\u4e00\u6761\u957f\u5ea6\u4e3a2.00\u7684\u9053\u8def\uff0c\u5728\u519c\u573a3\u548c\u519c\u573a4\u95f4\u5efa\u4e00
\n\u6761\u957f\u5ea6\u4e3a2.00\u7684\u9053\u8def\u3002\u8fd9\u6837\uff0c\u6240\u5efa\u9053\u8def\u7684\u603b\u957f\u4e3a4.00\uff0c\u5e76\u4e14\u8fd9\u662f\u6240\u6709\u65b9\u6848\u4e2d\u9053\u8def
\n\u603b\u957f\u6700\u5c0f\u7684\u4e00\u79cd\u3002<\/p>\n
<\/p>\n<\/div>\n
<\/span>HINT<\/span><\/h2>\n#include<map>\r\n#include<cmath>\r\n#include<queue>\r\n#include<cstdio>\r\n#include<cstring>\r\n#include<iostream>\r\n#include<algorithm>\r\nusing namespace std;\r\n#define ll long long\r\n#define N 1010\r\n#define db double\r\ninline int rd()\r\n{\r\n int x=0,f=1;char ch=getchar();\r\n while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}\r\n while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}\r\n return x*f;\r\n}\r\nstruct qaz{int a,b;db v;}e[N*N],q[N];\r\nbool cmp(qaz a,qaz b){return a.v<b.v;}\r\ndb dis(int a,int b)\r\n{\r\n ll x=q[a].a-q[b].a,y=q[a].b-q[b].b;\r\n return sqrt(x*x+y*y);\r\n}\r\nint cnt,fa[N];\r\nvoid add(int a,int b){e[++cnt]=(qaz){a,b,dis(a,b)};}\r\nint findf(int x){return x==fa[x]?x:fa[x]=findf(fa[x]);}\r\nint n,m,x,y;\r\ndb ans;\r\nint main()\r\n{\r\n n=rd();m=rd();\r\n int i,j,f1,f2;\r\n for(i=1;i<=n;i++)\r\n {\r\n q[i].a=rd();q[i].b=rd();\r\n fa[i]=i;\r\n }\r\n for(i=1;i<=m;i++)\r\n {\r\n x=rd();y=rd();\r\n x=findf(x);y=findf(y);\r\n fa[y]=x;\r\n }\r\n for(int i=1;i<=n;i++) fa[i]=findf(i);\r\n for(i=1;i<=n;i++)\r\n {\r\n for(j=1;j<=n;j++)\r\n {\r\n if(i==j) continue;\r\n if(fa[i]!=fa[j]) add(i,j);\r\n }\r\n }\r\n sort(e+1,e+cnt+1,cmp);\r\n for(int i=1;i<=cnt;i++)\r\n {\r\n x=findf(e[i].a);y=findf(e[i].b);\r\n if(x!=y)\r\n {\r\n ans+=e[i].v;\r\n fa[y]=x;\r\n }\r\n }\r\n printf(\"%.2lf\\n\",ans);\r\n return 0;\r\n}<\/pre>\n <\/p>\n","protected":false},"excerpt":{"rendered":"
1626: [Usaco2007 Dec]Building Roads \u4fee\u5efa\u9053\u8def Time Li […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[56],"class_list":["post-521","post","type-post","status-publish","format-standard","hentry","category-bzoj","tag-56"],"_links":{"self":[{"href":"https:\/\/blog.kylelv.com\/index.php?rest_route=\/wp\/v2\/posts\/521","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.kylelv.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.kylelv.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.kylelv.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.kylelv.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=521"}],"version-history":[{"count":2,"href":"https:\/\/blog.kylelv.com\/index.php?rest_route=\/wp\/v2\/posts\/521\/revisions"}],"predecessor-version":[{"id":523,"href":"https:\/\/blog.kylelv.com\/index.php?rest_route=\/wp\/v2\/posts\/521\/revisions\/523"}],"wp:attachment":[{"href":"https:\/\/blog.kylelv.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=521"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.kylelv.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=521"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.kylelv.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=521"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}