HDU 1512 (左偏树，合并堆)

#include<iostream>
#include<cstring>
#include<algorithm>
#include<cstdlib>
#include<vector>
#include<cmath>
#include<stdlib.h>
#include<iomanip>
#include<list>
#include<deque>
#include<map>
#include <stdio.h>
#include <deque>

#define maxn 20005
#define ull unsigned long long
#define rep(i,n) for(i=0;i<n;i++)
#define cle(a) memset(a,0,sizeof(a))

using namespace std;

const ull inf = 1LL << 61;

bool cmp(int a,int b){
return a>b;
}
#define typec int       // type of key val
#define N 100005
int zabs(int x) {
if (x < 0) return -x;
else return x;
}
const int na = -1;
struct node { typec key; int l, r, f, dist; } tr
;
int ary
;
int tree
, size
, cunt
;
// 获得结点i的根
int iroot(int i) {
if (i == na) return i;
while (tr[i].f != na) i = tr[i].f;
return i;
}
// 合并两棵左偏树, param: rx ry (two root)
int merge(int rx, int ry) {
if (rx == na) return ry;
if (ry == na) return rx;
if (tr[rx].key < tr[ry].key) swap(rx, ry);//rx的根节点的值大于ry根节点的值
int r = merge(tr[rx].r, ry);
tr[rx].r = r; tr[r].f = rx;
if (tr[r].dist > tr[tr[rx].l].dist) swap(tr[rx].l, tr[rx].r);
if (tr[rx].r == na) tr[rx].dist = 0;
else tr[rx].dist = tr[tr[rx].r].dist + 1;
return rx;                          // return new root
}
// 插入一个新节点
int ins(int i, typec key, int root) {
tr[i].key = key;
tr[i].l = tr[i].r = tr[i].f = na;
tr[i].dist = 0;
return root = merge(root, i);       // return new root
}
// 删除某个结点
int del(int i) {
if (i == na) return i;
int x, y, l, r;
l = tr[i].l; r = tr[i].r; y = tr[i].f;
tr[i].l = tr[i].r = tr[i].f = na;
tr[x = merge(l, r)].f = y;
if (y != na && tr[y].l == i) tr[y].l = x;
if (y != na && tr[y].r == i) tr[y].r = x;
for ( ; y != na; x = y, y = tr[y].f) {
if (tr[tr[y].l].dist < tr[tr[y].r].dist)
swap(tr[y].l, tr[y].r);
if (tr[tr[y].r].dist + 1 == tr[y].dist) break;
tr[y].dist = tr[tr[y].r].dist + 1;
}
if (x != na) return iroot(x);       // return new root
else return iroot(y);
}
// 获取最小结点
node top(int root) {
return tr[root];
}
// 取得并删除最小结点
int pop(int root) {
int l = tr[root].l, r = tr[root].r;
tr[root].l = tr[root].r = tr[root].f = na;
tr[l].f = tr[r].f = na;
return merge(l, r);
// return root;
}
// 增/减一个结点的键值
int add(int i, typec val) {
if (i == na) return i;
if (tr[i].l == na && tr[i].r == na && tr[i].f == na) {
tr[i].key += val;
return i;
}
typec key = tr[i].key + val;
int rt = del(i);
return ins(i, key, rt);
}
// 初始化数据
void init(int n) {
for (int i = 0; i < n; i++) {
scanf("%d", &ary[i]);
tr[i].key = ary[i];
tr[i].l = tr[i].r = tr[i].f = na;
tr[i].dist = 0;
}
}

int main() {
//freopen("in.txt","r",stdin);
//  freopen("out.txt","w",stdout);
int n;
while (scanf("%d", &n)!=EOF) {
init(n);
int m;cin>>m;
while(m--)
{

int x,y;
scanf("%d%d",&x,&y);
//   cin>>x>>y;//注意输入，用cin超时，但是我不知道为什么差距这么大
x--,y--;
x=iroot(x),y=iroot(y);//取得根节点
if(x!=y){
tr[x].key/=2;
tr[y].key/=2;
int px,py;
px=pop(x),py=pop(y);
px=merge(px,x),py=merge(py,y);
int ans=merge(px,py);
printf("%d\n",tr[ans].key);
//  cout<<tr[ans].key<<endl;
}
else printf("-1\n");
}
}
return 0;
}