loj2055 「TJOI / HEOI2016」排序

ref

#include <iostream>
#include <cstring>
#include <cstdio>
using namespace std;
int n, m, a[100005], sum[400005], tag[400005], q;
struct Node{
	int opt, lll, rrr;
}nd[100005];
void pushDown(int o, int l, int r, int lson, int rson, int mid){
	tag[lson] = tag[rson] = tag[o];
	sum[lson] = (mid - l + 1) * tag[o];
	sum[rson] = (r - mid) * tag[o];
	tag[o] = -1;
}
void modify(int o, int l, int r, int x, int y, int k){
	if(x>y)	return ;
	if(l>=x && r<=y){
		sum[o] = (r - l + 1) * k;
		tag[o] = k;
	}
	else{
		int mid=(l+r)>>1;
		int lson=o<<1;
		int rson=lson|1;
		if(tag[o]!=-1)	pushDown(o, l, r, lson, rson, mid);
		if(x<=mid)	modify(lson, l, mid, x, y, k);
		if(mid<y)	modify(rson, mid+1, r, x, y, k);
		sum[o] = sum[lson] + sum[rson];
	}
}
int query(int o, int l, int r, int x, int y){
	if(x>y)	return 0;
	if(l>=x && r<=y)	return sum[o];
	else{
		int mid=(l+r)>>1;
		int lson=o<<1;
		int rson=lson|1;
		if(tag[o]!=-1)	pushDown(o, l, r, lson, rson, mid);
		int re=0;
		if(x<=mid)	re += query(lson, l, mid, x, y);
		if(mid<y)	re += query(rson, mid+1, r, x, y);
		return re;
	}
}
bool chk(int lim){
	memset(sum, 0, sizeof(sum));
	memset(tag, -1, sizeof(tag));
	for(int i=1; i<=n; i++)
		if(a[i]>lim)
			modify(1, 1, n, i, i, 1);
	for(int i=1; i<=m; i++){
		int x=query(1, 1, n, nd[i].lll, nd[i].rrr);
		if(nd[i].opt){
			modify(1, 1, n, nd[i].lll, nd[i].lll+x-1, 1);
			modify(1, 1, n, nd[i].lll+x, nd[i].rrr, 0);
		}
		else{
			x = nd[i].rrr - nd[i].lll + 1 - x;
			modify(1, 1, n, nd[i].lll, nd[i].lll+x-1, 0);
			modify(1, 1, n, nd[i].lll+x, nd[i].rrr, 1);
		}

	}
	return query(1, 1, n, q, q)==0;
}
int main(){
	cin>>n>>m;
	for(int i=1; i<=n; i++)
		scanf("%d", &a[i]);
	for(int i=1; i<=m; i++)
		scanf("%d %d %d", &nd[i].opt, &nd[i].lll, &nd[i].rrr);
	cin>>q;
	int l=1, r=n, mid, re;
	while(l<=r){
		mid = (l + r) >> 1;
		if(chk(mid))	re = mid, r = mid - 1;
		else	l = mid + 1;
	}
	cout<<re<<endl;
	return 0;
}