{"id":273,"date":"2010-06-04T19:46:00","date_gmt":"2010-06-04T11:46:00","guid":{"rendered":"http:\/\/localhost\/?p=273"},"modified":"2010-06-04T19:46:00","modified_gmt":"2010-06-04T11:46:00","slug":"jsoi2008_minimum_spanning_tree_count","status":"publish","type":"post","link":"https:\/\/www.shuizilong.com\/wjmzbmr\/?p=273","title":{"rendered":"[JSOI2008]\u6700\u5c0f\u751f\u6210\u6811\u8ba1\u6570"},"content":{"rendered":"\n

[JSOI2008]\u6700\u5c0f\u751f\u6210\u6811\u8ba1\u6570<\/p>\n

Time Limit:1000MS Memory Limit:165536K
Total Submit:100 Accepted:38<\/p>\n

Description <\/strong><\/p>\n

\u73b0\u5728\u7ed9\u51fa\u4e86\u4e00\u4e2a\u7b80\u5355\u65e0\u5411\u52a0\u6743\u56fe\u3002\u4f60\u4e0d\u6ee1\u8db3\u4e8e\u6c42\u51fa\u8fd9\u4e2a\u56fe\u7684\u6700\u5c0f\u751f\u6210\u6811\uff0c\u800c\u5e0c\u671b\u77e5\u9053\u8fd9\u4e2a\u56fe\u4e2d\u6709\u591a\u5c11\u4e2a\u4e0d\u540c\u7684\u6700\u5c0f\u751f\u6210\u6811\u3002\uff08\u5982\u679c\u4e24\u9897\u6700\u5c0f\u751f\u6210\u6811\u4e2d\u81f3\u5c11\u6709\u4e00\u6761\u8fb9\u4e0d\u540c\uff0c\u5219\u8fd9\u4e24\u4e2a\u6700\u5c0f\u751f\u6210\u6811\u5c31\u662f\u4e0d\u540c\u7684\uff09\u3002\u7531\u4e8e\u4e0d\u540c\u7684\u6700\u5c0f\u751f\u6210\u6811\u53ef\u80fd\u5f88\u591a\uff0c\u6240\u4ee5\u4f60\u53ea\u9700\u8981\u8f93\u51fa\u65b9\u6848\u6570\u5bf931011\u7684\u6a21\u5c31\u53ef\u4ee5\u4e86\u3002 <\/p>\n

Input <\/strong><\/p>\n

\u7b2c\u4e00\u884c\u5305\u542b\u4e24\u4e2a\u6570\uff0cn\u548cm\uff0c\u5176\u4e2d1<=n<=100; 1<=m<=1000; \u8868\u793a\u8be5\u65e0\u5411\u56fe\u7684\u8282\u70b9\u6570\u548c\u8fb9\u6570\u3002\u6bcf\u4e2a\u8282\u70b9\u75281~n\u7684\u6574\u6570\u7f16\u53f7\u3002
\u63a5\u4e0b\u6765\u7684m\u884c\uff0c\u6bcf\u884c\u5305\u542b\u4e24\u4e2a\u6574\u6570\uff1aa, b, c\uff0c\u8868\u793a\u8282\u70b9a, b\u4e4b\u95f4\u7684\u8fb9\u7684\u6743\u503c\u4e3ac\uff0c\u5176\u4e2d1<=c<=1,000,000,000\u3002\u6570\u636e\u4fdd\u8bc1\u4e0d\u4f1a\u51fa\u73b0\u81ea\u56de\u8fb9\u548c\u91cd\u8fb9\u3002
\u6ce8\u610f\uff1a\u5177\u6709\u76f8\u540c\u6743\u503c\u7684\u8fb9\u4e0d\u4f1a\u8d85\u8fc710\u6761\u3002 <\/p>\n

Output <\/strong><\/p>\n

\u8f93\u51fa\u4e0d\u540c\u7684\u6700\u5c0f\u751f\u6210\u6811\u6709\u591a\u5c11\u4e2a\u3002\u4f60\u53ea\u9700\u8981\u8f93\u51fa\u6570\u91cf\u5bf931011\u7684\u6a21\u5c31\u53ef\u4ee5\u4e86\u3002 <\/p>\n

Sample Input <\/strong><\/p>\n<\/p>\n

Sample Output <\/strong><\/p>\n<\/p>\n

Source
\u8fd9\u9898\u662f\u8001\u9898\u4e86\u3002\u3002\u672c\u6765\u60f3A\u6389\u723d\u4e00\u4e0b\u7684\uff0c\u7ed3\u679cWA\u534a\u5929\uff0c\u6700\u540e\u53d1\u73b0\u8fd8\u53ef\u80fd\u6709\u65e0\u751f\u6210\u6811\u7684\u60c5\u51b5\u56e7\u3002\u3002\u3002
\u3002\u3002\u7b97\u6cd5\u7684\u8bdd\u5f88\u663e\u7136\u5bf9\u4e8e\u6240\u6709\u4e00\u7ec4\u6743\u503c\u76f8\u540c\u7684\u8fb9\uff0c\u5b83\u4eec\u4ee5\u6700\u5927\u6570\u91cf\u52a0\u5165\u4e4b\u540e\uff0c\u9020\u6210\u7684\u8fde\u901a\u6027\u662f\u4e00\u6837\u7684\uff0c\u90a3\u4e48\u4ece\u5c0f\u5230\u5927\u7b97\u51fa\u6bcf\u4e00\u7ec4\u8fb9\uff0c\u4e58\u8d77\u6765\u5c31OK\u4e86\u3002\u3002
\u5982\u679c\u6570\u636e\u5927\u4e00\u70b9\u7684\u8bdd\u53ea\u597d\u7528\u77e9\u9635\u6765\u7b97\u7b54\u6848\u4e86\u3002\u3002\u4e0d\u8fc7\u8fd9\u91cc\u8303\u56f4\u8fd9\u4e48\u5c0f\u66b4\u529b\u5c31OK\u4e86\u3002\u3002\u3002
Code\uff1a
#include <vector><\/strong>
#include <iostream>
#include <map>
#include <utility>
#define rep(i,n) for(int i=0;i<n;i++)
#define pb push_back
const int mod=31011,maxn=100,maxm=1000;
using namespace std;
typedef pair<int,int> ii;
struct UF
{
    int F[maxn];
    void clear(){rep(i,maxn)F[i]=i;}
    int find(int x)
    {
        if(F[x]==x)return x;
        return F[x]=find(F[x]);
    }
    bool Union(int i,int j)
    {
        i=find(i);j=find(j);
        return F[i]=j,i!=j;
    }
    UF& operator=(const UF&u)
    {
        memcpy(F,u.F,sizeof(F));
        return *this;
    }
};
int n,m,ans=1,get,ret;
typedef map<int,vector<ii> >::iterator mit;
map<int,vector<ii> > M;
UF All,Link;
vector<ii> now;
void Dfs(int p,int c)
{
    if(p==now.size())
    {
        if(c==get)ret++;
        return;
    }
    ii t=now[p];UF tmp=Link;
    if(Link.Union(t.first,t.second))Dfs(p+1,c+1);
    Link=tmp;
    Dfs(p+1,c);
}
int main()
{
    cin>>n>>m;int s,t,c;
    rep(i,m)
    {
        cin>>s>>t>>c;s–;t–;
        M.pb(ii(s,t));
    }
    All.clear();s=0;
    for(mit i=M.begin();i!=M.end();i++)
    {
        now=i->second;Link=All;get=0;ret=0;
        rep(j,now.size())get+=All.Union(now[j].first,now[j].second);
        Dfs(0,0);ans*=ret;ans%=mod;s+=get;
    }<\/strong>
    if(s<n-1)cout<<0<<endl;
    else cout<<ans<<endl;
}<\/p>\n

84 61 2 11 3 11 4 12 3 22 4 13 4 1 <\/p>\n","protected":false},"excerpt":{"rendered":"

[JSOI2008]\u6700\u5c0f\u751f\u6210\u6811\u8ba1\u6570 Time Limit:1000MS Memory Limit:165536KTotal Submit:100 Accepted:38 Description \u73b0\u5728\u7ed9\u51fa\u4e86\u4e00\u4e2a\u7b80\u5355\u65e0\u5411\u52a0\u6743\u56fe\u3002\u4f60\u4e0d\u6ee1\u8db3\u4e8e\u6c42\u51fa\u8fd9\u4e2a\u56fe\u7684\u6700\u5c0f\u751f\u6210\u6811\uff0c\u800c\u5e0c\u671b\u77e5\u9053\u8fd9\u4e2a\u56fe\u4e2d\u6709\u591a\u5c11\u4e2a\u4e0d\u540c\u7684\u6700\u5c0f\u751f\u6210\u6811\u3002\uff08\u5982\u679c\u4e24\u9897\u6700\u5c0f\u751f\u6210\u6811\u4e2d\u81f3\u5c11\u6709\u4e00\u6761\u8fb9\u4e0d\u540c\uff0c\u5219\u8fd9\u4e24\u4e2a\u6700\u5c0f\u751f\u6210\u6811\u5c31\u662f\u4e0d\u540c\u7684\uff09\u3002\u7531\u4e8e\u4e0d\u540c\u7684\u6700\u5c0f\u751f\u6210\u6811\u53ef\u80fd\u5f88\u591a\uff0c\u6240\u4ee5\u4f60\u53ea\u9700\u8981\u8f93\u51fa\u65b9\u6848\u6570\u5bf931011\u7684\u6a21\u5c31\u53ef\u4ee5\u4e86\u3002 Input \u7b2c\u4e00\u884c\u5305\u542b\u4e24\u4e2a\u6570\uff0cn\u548cm\uff0c\u5176\u4e2d1<=n<=100; 1<=m<=1000; \u8868\u793a\u8be5\u65e0\u5411\u56fe\u7684\u8282\u70b9\u6570\u548c\u8fb9\u6570\u3002\u6bcf\u4e2a\u8282\u70b9\u75281~n\u7684\u6574\u6570\u7f16\u53f7\u3002 \u63a5\u4e0b\u6765\u7684m\u884c\uff0c\u6bcf\u884c\u5305\u542b\u4e24\u4e2a\u6574\u6570\uff1aa, b, c\uff0c\u8868\u793a\u8282\u70b9a, b\u4e4b\u95f4\u7684\u8fb9\u7684\u6743\u503c\u4e3ac\uff0c\u5176\u4e2d1<=c<=1,000,000,000\u3002\u6570\u636e\u4fdd\u8bc1\u4e0d\u4f1a\u51fa\u73b0\u81ea\u56de\u8fb9\u548c\u91cd\u8fb9\u3002 \u6ce8\u610f\uff1a\u5177\u6709\u76f8\u540c\u6743\u503c\u7684\u8fb9\u4e0d\u4f1a\u8d85\u8fc710\u6761\u3002 Output \u8f93\u51fa\u4e0d\u540c\u7684\u6700\u5c0f\u751f\u6210\u6811\u6709\u591a\u5c11\u4e2a\u3002\u4f60\u53ea\u9700\u8981\u8f93\u51fa\u6570\u91cf\u5bf931011\u7684\u6a21\u5c31\u53ef\u4ee5\u4e86\u3002 Sample Input Sample Output Source \u8fd9\u9898\u662f\u8001\u9898\u4e86\u3002\u3002\u672c\u6765\u60f3A\u6389\u723d\u4e00\u4e0b\u7684\uff0c\u7ed3\u679cWA\u534a\u5929\uff0c\u6700\u540e\u53d1\u73b0\u8fd8\u53ef\u80fd\u6709\u65e0\u751f\u6210\u6811\u7684\u60c5\u51b5\u56e7\u3002\u3002\u3002\u3002\u3002\u7b97\u6cd5\u7684\u8bdd\u5f88\u663e\u7136\u5bf9\u4e8e\u6240\u6709\u4e00\u7ec4\u6743\u503c\u76f8\u540c\u7684\u8fb9\uff0c\u5b83\u4eec\u4ee5\u6700\u5927\u6570\u91cf\u52a0\u5165\u4e4b\u540e\uff0c\u9020\u6210\u7684\u8fde\u901a\u6027\u662f\u4e00\u6837\u7684\uff0c\u90a3\u4e48\u4ece\u5c0f\u5230\u5927\u7b97\u51fa\u6bcf\u4e00\u7ec4\u8fb9\uff0c\u4e58\u8d77\u6765\u5c31OK\u4e86\u3002\u3002\u5982\u679c\u6570\u636e\u5927\u4e00\u70b9\u7684\u8bdd\u53ea\u597d\u7528\u77e9\u9635\u6765\u7b97\u7b54\u6848\u4e86\u3002\u3002\u4e0d\u8fc7\u8fd9\u91cc\u8303\u56f4\u8fd9\u4e48\u5c0f\u66b4\u529b\u5c31OK\u4e86\u3002\u3002\u3002Code\uff1a#include <vector>#include <iostream>#include <map>#include <utility>#define rep(i,n) for(int i=0;i<n;i++)#define pb push_backconst int mod=31011,maxn=100,maxm=1000;using namespace std;typedef pair<int,int> ii;struct UF{    int F[maxn];    void clear(){rep(i,maxn)F[i]=i;}    int find(int x)    {        if(F[x]==x)return x;        return F[x]=find(F[x]);    }    […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[10],"tags":[],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=\/wp\/v2\/posts\/273"}],"collection":[{"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=273"}],"version-history":[{"count":0,"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=\/wp\/v2\/posts\/273\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=273"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=273"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.shuizilong.com\/wjmzbmr\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=273"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}