[JSOI2008]Blue Mary开公司[李超线段树]

题面

bzoj
luogu

好久以前听lxl讲过 咕掉了。。 竟然又遇到了
安利blog

#include <cmath>
#include <cstring>
#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <complex>
#include <ctime>
#include <vector>
#define mp(x, y) make_pair(x, y)
using namespace std;
const int N = 1e5 + 5;
const int n = 5e4 + 2;
const double eps = 1e-9;
struct Line{
	double k, b;
	double f(double x){return k * x + b;}
}line[N];
int lsize;
struct LCSeg{
	int w[N << 2];
	void ins(int rt, int l, int r, int id){
		if(!w[rt]){w[rt] = id; return ;}
		if(l == r){
			if(line[id].f(l) > line[w[rt]].f(l)) w[rt] = id; 
			return ;
		}
	    int mid = l + ((r - l) >> 1);
	    if(line[id].k > line[w[rt]].k){
	    	if(line[id].f(mid) > line[w[rt]].f(mid)) ins(rt << 1, l, mid, w[rt]), w[rt] = id;
	    	else ins(rt << 1 | 1, mid + 1, r, id);
	    }
	    else {
	    	if(line[id].f(mid) > line[w[rt]].f(mid)) ins(rt << 1 | 1, mid + 1, r, w[rt]), w[rt] = id;
	    	else ins(rt << 1, l, mid, id);
	    }//这边要好好推 
	}
	double qry(int rt, int l, int r, int x){
		if(l == r) return line[w[rt]].f(x);
		double res = line[w[rt]].f(x);
		int mid = l + ((r - l) >> 1);
		if(x <= mid) res = max(res, qry(rt << 1, l, mid, x));
		else res = max(res, qry(rt << 1 | 1, mid + 1, r, x));
		return res;
	}
}seg;
int main(){
	int T, pos; double x, y; char ss[N];
	scanf("%d", &T); 
	while(T--){
		scanf("%s", ss);
		if(ss[0] == 'Q'){
			scanf("%d", &pos);
		    double res = seg.qry(1, 1, n, pos);
			printf("%d\n", (int)res / 100);
		}
		else {
			++lsize;
			scanf("%lf%lf", &line[lsize].b, &line[lsize].k); line[lsize].b -= line[lsize].k;
			seg.ins(1, 1, n, lsize);
		}
	} 
    return 0;	
}