BZOJ 1208 HNOI2004 宠物收容所 平衡树/set

标题效果：有一个宠物收容所。目前还没有被采纳的宠物或谁想要领养宠物，每个宠物有个性值，大家谁想要领养宠物具有理想人格值。每一刻，宠物收容所只是为了有谁想要领养宠物或宠物的人。

当领走宠物，将有一定程度的不愉快。最低要求是不舒服程度。

思路：就是个模拟+数据结构维护。用set能够水过，时间卡的不是非常紧。练手写了Treap。

注意极大值不能开太大。会re

CODE：

#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
#define INF 0x3f3f3f3f
using namespace std;

struct Complex{
	int val,random,cnt,size;
	Complex *son[2];

	Complex() {
		son[0] = son[1] = NULL;
		random = rand();
		cnt = size = 1;
	}
	void Maintain() {
		size = cnt;
		if(son[0] != NULL)	size += son[0]->size;
		if(son[1] != NULL)	size += son[1]->size;
	}
	int Compare(int x) {
		if(x == val)	return -1;
		return x > val;
	}
}*root; 

int cnt,ans;
int total;

int flag;

inline void Rotate(Complex *&a,bool dir);
void Insert(Complex *&a,int x);
void Delete(Complex *&a,int x);
int FindSucc(Complex *a,int x);
int FindPred(Complex *a,int x);

int main()
{
	cin >> cnt;
	for(int x,i = 1;i <= cnt; ++i) {
		scanf("%d%d",&flag,&x);
		if(total > 0) {
			if(flag)	Insert(root,x),total++;
			else {
				int pred = FindPred(root,x);
				int succ = FindSucc(root,x);
				int will_delete = (x - pred <= succ - x) ?

pred:succ; Delete(root,will_delete); total--; ans += abs(will_delete - x); } } else if(total < 0) { if(!flag) Insert(root,x),total--; else { int pred = FindPred(root,x); int succ = FindSucc(root,x); int will_delete = (x - pred <= succ - x) ? pred:succ; Delete(root,will_delete); total++; ans += abs(will_delete - x); } } else Insert(root,x),total = (flag ? 1:-1); ans %= 1000000; } cout << ans << endl; return 0; } inline void Rotate(Complex *&a,bool dir) { Complex *k = a->son[!dir]; a->son[!dir] = k->son[dir]; k->son[dir] = a; a->Maintain(),k->Maintain(); a = k; } void Insert(Complex *&a,int x) { if(a == NULL) { a = new Complex(); a->val = x; return ; } int dir = a->Compare(x); if(dir == -1) a->cnt++; else { Insert(a->son[dir],x); if(a->son[dir]->random > a->random) Rotate(a,!dir); } a->Maintain(); } void Delete(Complex *&a,int x) { int dir = a->Compare(x); if(dir != -1) Delete(a->son[dir],x); else { if(a->cnt > 1) a->cnt--; else { if(a->son[0] == NULL) a = a->son[1]; else if(a->son[1] == NULL) a = a->son[0]; else { bool _dir = (a->son[0]->random > a->son[1]->random); Rotate(a,_dir); Delete(a->son[_dir],x); } } } if(a != NULL) a->Maintain(); } int FindPred(Complex *a,int x) { if(a == NULL) return -INF; if(a->val > x) return FindPred(a->son[0],x); return max(a->val,FindPred(a->son[1],x)); } int FindSucc(Complex *a,int x) { if(a == NULL) return INF; if(a->val < x) return FindSucc(a->son[1],x); return min(a->val,FindSucc(a->son[0],x)); }

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