luogu4169 [Violet]天使玩偶/SJY摆棋子 / bzoj2648 SJY摆棋子 k-d tree

k-d tree + 重构的思想,就能卡过luogu和bzoj啦orz

#include <algorithm>
#include <iostream>
#include <cstdio>
using namespace std;
int n, m, rot, nowD, opt, uu, vv, ans, rub[1000005], din, cur;
const double aph=0.65;
struct Point{
	int d[2], mn[2], mx[2], l, r, siz;
	int & operator[](int x){
		return d[x];
	}
	bool operator<(const Point &x)const{
		return d[nowD]<x.d[nowD];
	}
	Point(int x=0, int y=0){
		l = r = siz = 0;
		d[0] = x; d[1] = y;
	}
}p[1000005];
int getDis(Point x, Point y){
	return abs(x[1]-y[1])+abs(x[0]-y[0]);
}
struct KDTree{
	Point t[1000005], T;
	void pushUp(int x){
		Point l=t[t[x].l], r=t[t[x].r];
		for(int i=0; i<2; i++){
			t[x].mn[i] = t[x].mx[i] = t[x][i];
			if(t[x].l){
				t[x].mn[i] = min(t[x].mn[i], l.mn[i]);
				t[x].mx[i] = max(t[x].mx[i], l.mx[i]);
			}
			if(t[x].r){
				t[x].mn[i] = min(t[x].mn[i], r.mn[i]);
				t[x].mx[i] = max(t[x].mx[i], r.mx[i]);
			}
		}
		t[x].siz = l.siz + r.siz + 1;
	}
	int newNode(){
		if(din)	return rub[din--];
		else	return ++cur;
	}
	int build(int l, int r, int now){
		nowD = now;
		int mid=(l+r)>>1, k=newNode();
		nth_element(p+l, p+mid, p+1+r);
		t[k] = p[mid];
		t[k].l = t[k].r = t[k].siz = 0;
		if(l<mid)	t[k].l = build(l, mid-1, now^1);
		if(mid<r)	t[k].r = build(mid+1, r, now^1);
		pushUp(k);
		return k;
	}
	void pia(int k, int num){
		if(t[k].l)	pia(t[k].l, num);
		p[num+t[t[k].l].siz+1] = t[k]; 
		rub[++din] = k;
		if(t[k].r)	pia(t[k].r, num+t[t[k].l].siz+1);
	}
	void chkPia(int &k, int now){
		if(aph*t[k].siz<t[t[k].l].siz || aph*t[k].siz<t[t[k].r].siz){
			pia(k, 0);
			k = build(1, t[k].siz, now);
		}
	}
	void insert(int &k, int now){
		if(!k){
			k = newNode();
			t[k] = T;
			t[k].l = t[k].r = 0;
			pushUp(k);
			return ;
		}
		if(T[now]>=t[k][now])	insert(t[k].r, now^1);
		else	insert(t[k].l, now^1);
		pushUp(k);
		chkPia(k, now);
	}
	int get(int k, Point p){
		int re=0;
		for(int i=0; i<2; i++)
			re += max(0, p[i]-t[k].mx[i]);
		for(int i=0; i<2; i++)
			re += max(0, t[k].mn[i]-p[i]);
		return re;
	}
	void query(int k, int now){
		int d=getDis(t[k],T), dl=0x3f3f3f3f, dr=0x3f3f3f3f;
		ans = min(ans, d);
		if(t[k].l)	dl = get(t[k].l, T);
		if(t[k].r)	dr = get(t[k].r, T);
		if(dl<dr){
			if(dl<ans)	query(t[k].l, now^1);
			if(dr<ans)	query(t[k].r, now^1);
		}
		else{
			if(dr<ans)	query(t[k].r, now^1);
			if(dl<ans)	query(t[k].l, now^1);
		}
	}
}kdt;
void rn(int &x){
	char ch=getchar();
	x = 0;
	while(ch<'0' || ch>'9')	ch = getchar();
	while(ch>='0' && ch<='9'){
		x = x * 10 + ch - '0';
		ch = getchar();
	}
}
int main(){
	cin>>n>>m;
	for(int i=1; i<=n; i++){
		rn(p[i][0]);
		rn(p[i][1]);
	}
	rot = kdt.build(1, n, 0);
	while(m--){
		scanf("%d %d %d", &opt, &uu, &vv);
		kdt.T = Point(uu, vv);
		if(opt==1)
			kdt.insert(rot, 0);
		else{
			ans = 0x3f3f3f3f;
			kdt.query(rot, 0);
			printf("%d
", ans);
		}
	}
	return 0;
}
原文地址:https://www.cnblogs.com/poorpool/p/8949401.html