> #include <iostream>
> #include <cstdio>
> #include <cmath>
> using namespace  std;
> const int maxn = 30010;
> int a[maxn],f[maxn];
> int findx(int x){
>     return f[x]<0?x:f[x]=findx(f[x]);
> }
> void bing(int a,int b){
>     int t1 = findx(a);
>     int t2 = findx(b);
>     if(t1!=t2){
>        if(t2==0){
>         f[t2]+=f[t1];
>         f[t1] = t2;
>     }
>     else{
>         f[t1]+=f[t2];
>         f[t2] = t1;
>     }
>     }
> }
> int main(){
>     int n,m;
>     while(scanf("%d%d",&n,&m)!=EOF){
>         if(n==0&&m==0)
>             break;
>         for(int i=0;i<n;++i) f[i] = -1;
>         for(int i=1;i<=m;++i){
>             int k;
>             scanf("%d",&k);
>             int t;
>             for(int i=1;i<=k;++i){
>                 if(i==1){
>                     scanf("%d",&t);
>                     continue;
>                 }
>                 int s;
>                 scanf("%d",&s);
>                 bing(s,t);
>             }
>         }
>         cout << abs(f[0])<<endl;
>     }
>     return 0;
> }

• Re:经典并查集,16ms (2) 703160327 2020-03-28 13:40:26