并查集模板

const int N=120;
int father[N];
int rank1[N];
void init(int Size)
{
    for(int i=1;i<=Size;++i)
        father[i]=i,rank1[i]=0;

}
int Find(int x)
{
    while(x!=father[x])
        x=father[x];
    return x;
}
bool Union(int x,int y)
{
    int fx,fy;
    fx=Find(x),fy=Find(y);
    if(fx==fy)
        return false;
    else if(rank1[fx]>=rank1[fy])
    {
        father[fy]=fx;
        rank1[fx]+=rank1[fy];
    }
    else
    {
        father[fx]=fy;
        rank1[fy]+=rank1[fx];
    }
    return true;
}

int Find(int x)
{
    return x==f[x]?x:f[x]=Find(f[x]);
}
void Union(int x,int y)
{
    x=Find(x),y=Find(y);
    if(x!=y) f[x]=y;
}

并查集的删除节点操作

　　HDU-2473  Junk-Mail Filter

#include <iostream>
#include<algorithm>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <queue>
#include<map>
#include<set>
#include<sstream>
#define INF 0x3f3f3f3f
#define DOF 0x7f7f7f7f
#define mem(a,b) memset(a,b,sizeof(a))
#define IO ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
typedef long long ll;
using namespace std;
const int maxn=2e6+10;
int f[maxn],b[maxn],vis[maxn];//令一新数组表示儿子节点的值
int n,m;

int Find(int x){
    return f[x]==x?x:f[x]=Find(f[x]);
}
void Union(int x,int y)
{
    x=Find(x),y=Find(y);
    if(x!=y) f[x]=y;
}
int main()
{
    int cas=0;
    while(~scanf("%d%d",&n,&m)&&n){
        mem(vis,0);
        int cnt=n;
        for(int i=0;i<n;++i) f[i]=b[i]=i;
        char ch;int a,c;
        for(int i=1;i<=m;++i){
            getchar();
            scanf("%c",&ch);
            if(ch=='M'){
                scanf("%d%d",&a,&c);
                Union(b[a],b[c]);
            }
            else{
                scanf("%d",&a);
                f[cnt]=cnt;//将此节点指向外部数组，此数组代表此点的父节点位置
                b[a]=cnt;
                ++cnt;
            }
        }
        ll ans=0;
        for(int i=0;i<n;++i){
            int t=Find(b[i]);
            if(!vis[t]){
                vis[t]=1;++ans;
            }
        }
        printf("Case #%d: %lld
",++cas,ans);
    }
}