Data Center Maintenance CodeForces - 950E

http://codeforces.com/contest/950/problem/E

贴一份板子

 #include<cstdio>
 #include<vector>
 #include<algorithm>
 using namespace std;
 struct E
 {
     int to,nxt;
 }e[];
 int f1[],ne,a[],sccc,sccnum[],top,dfn[],low[],dfsc;
 int s[],n,m,h,ou[],anss=0x3f3f3f3f,ans1;
 vector<int> sccx[];
 void me(int u,int v)
 {
     e[++ne].to=v;
     e[ne].nxt=f1[u];
     f1[u]=ne;
 }

 void dfs(int u)
 {
     dfn[u]=low[u]=++dfsc;
     s[++top]=u;
     for(int k=f1[u],v;k!=;k=e[k].nxt)
     {
         v=e[k].to;
         if(!dfn[v])
         {
             dfs(v);
             low[u]=min(low[u],low[v]);
         }
         else if(!sccnum[v])
             low[u]=min(low[u],dfn[v]);
     }
     if(low[u]==dfn[u])
     {
         sccc++;
         while(top&&s[top]!=u)    sccnum[s[top--]]=sccc;
         sccnum[s[top--]]=sccc;
     }
 }

 int main()
 {
     int c1,c2,i,k;
     scanf("%d%d%d",&n,&m,&h);
     for(i=;i<=n;i++)    scanf("%d",&a[i]);
     for(i=;i<=m;i++)
     {
         scanf("%d%d",&c1,&c2);
         if((a[c1]+)%h==a[c2])    me(c1,c2);
         if((a[c2]+)%h==a[c1])    me(c2,c1);
     }
     for(i=;i<=n;i++)
         if(!dfn[i])
             dfs(i);
     for(i=;i<=n;i++)
         for(k=f1[i];k!=;k=e[k].nxt)
             if(sccnum[e[k].to]!=sccnum[i])
                 ou[sccnum[i]]++;
     for(i=;i<=n;i++)
         sccx[sccnum[i]].push_back(i);
     //printf("%da\n",ou[1]);
     for(i=;i<=sccc;i++)
         if(ou[i]==&&sccx[i].size()<anss)
         {
             anss=sccx[i].size();
             ans1=i;
         }
     printf("%d\n",anss);
     for(i=;i<anss;i++)    printf("%d ",sccx[ans1][i]);
     return ;
 }