Home Backend Development PHP Tutorial PHP operation MongoDB database summary record_PHP tutorial

PHP operation MongoDB database summary record_PHP tutorial

Jul 14, 2016 am 10:12 AM
mongodb php Summarize operate database Record

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#include<cstdio>

#include<cstring>

#include<vector>

using namespace std;

int vis[5000];

vector<int> map[5000];

int ans;

void dfs(int k,int num)

{

 

    vis[k]=num;     //相当于给每个结点编号

    for(int i=0;i<map[k].size();i++)

    {

        if(!vis[map[k][i]])

            dfs(map[k][i],num+1);

        else

        {

            int tmp=vis[k]-vis[map[k][i]]+1;//找到访问过的结点了,直接编号相减加1就是环的大小

            if(tmp>2&&tmp>ans)

            ans=tmp;

        }

    }

}

int main()

{

    int n,m,a,b,c;

    int cas;

    scanf("%d",&cas);

    while(cas--)

    {

        ans=0;

        scanf("%d%d",&n,&m);

        for(int i=1;i<=n;i++)

        {

            map[i].clear();

        }

        for(int i=1;i<=m;i++)

        {

            scanf("%d%d",&a,&b);

            map[a].push_back(b);

            map[b].push_back(a);

        }

        memset(vis,0,sizeof(vis));

        for(int i=1;i<=n;i++)

        {

            if(!vis[i]);

            dfs(i,0);

        }

        printf("%d\n",ans);

    }

    return 0;

}

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www.bkjia.comtruehttp: //www.bkjia.com/PHPjc/477210.htmlTechArticle#includecstdio#includecstring#includevectorusing namespace std;int vis[5000];vectorint map[5000];int ans; void dfs(int k,int num){ vis[k]=num; //Equivalent to numbering each node for(i...
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