李超线段树 P4097 [HEOI2013]Segment

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题链

向下推的时候是类似向下推懒惰标记的方式，没理解导致吃了一整页的WA

#include <bits/stdc++.h>
//#include <ext/pb_ds/priority_queue.hpp>
//#pragma GCC optimize("O2")
using namespace std;
//using namespace __gnu_pbds;
#define Combine Pair, greater<Pair>, pairing_heap_tag
#define LL long long
#define ll long long
#define Pair pair<double,LL>
#define ULL unsigned long long
#define ls rt<<1
#define rs rt<<1|1
#define one first
#define two second
#define MS 1000009
#define INF 1e18
#define DBINF 1e100
#define Pi acos(-1.0)
#define eps 1e-9
#define mod 99999997
#define mod1 39989
#define mod2 1000000000

LL n,m;
struct node {
	double k,b;
} line[MS];
int tli;
int p[MS<<2];

double calc(int i,int x) {
	return line[i].k*x+line[i].b;
}

void push_down(int rt,int l,int r,int i) {
	int m = l+r>>1;
	int j = p[rt];
	double ci = calc(i,m);
	double cj = calc(j,m);
	if(!j){
		p[rt] = i;
		return;
	}
	if(l == r) {
		if(ci > cj) p[rt] = i;
		return;
	}
	if(line[i].k > line[j].k) {
		if(ci > cj) p[rt] = i ,push_down(ls,l,m,j); // 将原线段向下推 吃了一整页的 WA 
		else push_down(rs,m+1,r,i); 
	} 
	else if(line[i].k < line[j].k) {
		if(ci > cj) p[rt] = i ,push_down(rs,m+1,r,j); // 将原线段向下推 
		else push_down(ls,l,m,i);
	} 
	else {
		if(line[i].b > line[j].b) p[rt] = i;
	}
}

void update(int L,int R,int l,int r,int rt,int i){
	if(L <= l && r <= R){
		push_down(rt,l,r,i);
		return;
	}
	int m = l+r>>1;
	if(m >= L) update(L,R,l,m,ls,i);
	if(m <  R) update(L,R,m+1,r,rs,i);
}

Pair pmax(Pair t1,Pair t2) {
	if(t1.one > t2.one) return t1;
	else if(t1.one < t2.one) return t2;
	else return t1.two < t2.two ? t1:t2;
}

Pair get_line(int l,int r,int rt,int tar) {
	if(tar < l || tar > r) return {0,0};
	int m = l+r>>1;
	double cc = calc(p[rt],tar);
	if(l == r) return {cc,p[rt]};
	return pmax({cc,p[rt]},pmax(get_line(l,m,ls,tar),get_line(m+1,r,rs,tar)));
}

int main() {
	ios::sync_with_stdio(false);
	int lastans = 0;
	cin >> n;
	while(n--) {
		int op,tar;
		int x1,y1,x2,y2;
		cin >> op;
		if(op) {
			cin >> x1 >> y1 >> x2 >> y2;
			x1 = (x1+lastans-1+mod1)%mod1+1;
			y1 = (y1+lastans-1+mod2)%mod2+1;
			x2 = (x2+lastans-1+mod1)%mod1+1;
			y2 = (y2+lastans-1+mod2)%mod2+1;
			if(x1 > x2) swap(x1,x2) ,swap(y1,y2);
			++tli;
			if(x1 == x2){
				line[tli].k = 0;
				line[tli].b = max(y1,y2);
			}
			else{
				line[tli].k = 1.0*(y2-y1)/(x2-x1),
				line[tli].b = y1 - line[tli].k*x1; // 换一种写法会 WA... 
			}
			update(x1,x2,1,mod1,1,tli);
		} else {
			cin >> tar;
			tar = (tar+lastans-1+mod1)%mod1+1;
			lastans = get_line(1,mod1,1,tar).two;
			cout << lastans << endl;
		}
	}


	return 0;
}