[题目链接] https://www.luogu.org/problemnew/show/P3377
#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
const int INF=1e9+7;
inline LL read(){
register LL x=0,f=1;register char c=getchar();
while(c<48||c>57){if(c==‘-‘)f=-1;c=getchar();}
while(c>=48&&c<=57)x=(x<<3)+(x<<1)+(c&15),c=getchar();
return f*x;
}
const int MAXN=1e5+5;
struct Tree{
int val,ls,rs,rt,dis;
}a[MAXN];
int n,m;
inline int Getrt(int x){return x==a[x].rt?x:a[x].rt=Getrt(a[x].rt);}
inline int Merge(int x,int y){
if(!x||!y) return x+y;
if(a[x].val>a[y].val||(a[x].val==a[y].val&&x>y)) swap(x,y);
a[x].rs=Merge(a[x].rs,y);
if(a[a[x].ls].dis<a[a[x].rs].dis) swap(a[x].ls,a[x].rs);
a[x].rt=a[a[x].ls].rt=a[a[x].rs].rt=x;
a[x].dis=a[a[x].rs].dis+1;
return x;
}
inline void Pop(int x){
a[x].val=-1;
//a[a[x].ls].rt=a[a[x].rs].rt=Merge(a[x].ls,a[x].rs);
a[a[x].ls].rt=a[x].ls,a[a[x].rs].rt=a[x].rs;
a[x].rt=Merge(a[x].ls,a[x].rs);
}
int main(){
n=read(),m=read();
a[0].dis=-1;
for(int i=1;i<=n;i++)
a[i].val=read(),a[i].rt=i,a[i].ls=a[i].rs=0;
for(int i=1;i<=m;i++){
int op=read();
if(op==1){
int x=read(),y=read();
if(a[x].val==-1||a[y].val==-1) continue;
int fx=Getrt(x),fy=Getrt(y);
if(fx!=fy) a[fx].rt=a[fy].rt=Merge(fx,fy);
}
if(op==2){
int x=read(),fx=Getrt(x);
if(a[x].val==-1){
printf("%d\n",-1);
continue;
}
printf("%d\n",a[fx].val);
Pop(fx);
}
}
}
[数据加强版] https://www.luogu.org/problemnew/show/P2713
[代码] https://www.luogu.org/recordnew/show/16436151
原文:https://www.cnblogs.com/lizehon/p/10392260.html