左偏树

ref(orz Melacau):

https://www.cnblogs.com/Melacau/p/leftist_tree.html

Code(luogu 3377):

#include<cstdio>
#include<cstring>
#include<algorithm>
#define MN 100005
using namespace std;
inline int in(){
    int x=0;bool f=0; char c;
    for (;(c=getchar())<'0'||c>'9';f=c=='-');
    for (x=c-'0';(c=getchar())>='0'&&c<='9';x=(x<<3)+(x<<1)+c-'0');
    return f?-x:x;
}
int ch[2][MN],a[MN],d[MN],fa[MN];
int n,m,tp,x,y,fx,fy;
inline int gf(int x){return fa[x]?gf(fa[x]):x;}
inline int merge(int x,int y){
    if (!x) return y;if (!y) return x;
    if (a[x]>a[y]||(a[x]==a[y]&&x>y)) swap(x,y);
    ch[1][x]=merge(ch[1][x],y);fa[ch[1][x]]=x;
    if (d[ch[0][x]]<d[ch[1][x]]) swap(ch[0][x],ch[1][x]);
    d[x]=d[ch[1][x]]+1;return x;
}
inline void pop(int x){
    a[x]=-1;fa[ch[0][x]]=fa[ch[1][x]]=0;
    merge(ch[0][x],ch[1][x]);
}
int main()
{
    n=in();m=in();d[0]=-1;
    for (int i=1;i<=n;++i) a[i]=in();
    for (int i=1;i<=m;++i){
        tp=in();x=in();
        if (tp==1){
            y=in();if (a[x]==-1||a[y]==-1) continue;
            if (x==y) continue;
            fx=gf(x);fy=gf(y);merge(fx,fy);
        }else {
            if (a[x]==-1) puts("-1");
            else fx=gf(x),printf("%d
",a[fx]),pop(fx);
        }
    }return 0;
}