Submission #738336

#	Time	Username	Problem	Language	Result	Execution time	Memory
738336		bobthebuilder	Comparing Plants (IOI20_plants)	C++17	100 / 100	1206 ms	116072 KiB

plants

#include "plants.h"
#include<bits/stdc++.h>
using namespace std;
#define sz(x) (int)x.size()
#define REP(i,n) for(int i=0;i<n;i++)
#define REP1(i,n) for(int i=1;i<=n;i++)
#define pb push_back
#define lowb(x) (x&(-x))
#define ALL(_x) _x.begin(),_x.end()
#define pii pair<int,int>
#define f first
#define s second
#define SORT_UNIQUE(x) sort(ALL(x)),x.erase(unique(ALL(x)),x.end())
#define ll long long
#define MNTO(x,y) x=min(x,y)
#define MXTO(x,y) x=max(x,y)
const int maxn=2e5+5;
const int INF=0x3f3f3f3f;
namespace {
int seg[4*maxn],pos[4*maxn];
int arr[maxn];
int lazy[4*maxn];
int ans[2*maxn];
int cur;
int k;
int n;
}
void pushdown(int idx,int l,int r){
	if(!lazy[idx]){
		return;
	}
	seg[idx]+=lazy[idx];
	if(l==r){
		lazy[idx]=0;
		return;
	}
	lazy[idx*2]+=lazy[idx];
	lazy[idx*2+1]+=lazy[idx];
	lazy[idx]=0;
}
void build(int idx,int l,int r){
	
	if(l==r){
		seg[idx]=arr[l];
		pos[idx]=l;
		return;
	}
	int mid=(l+r)/2;
	build(idx*2,l,mid),build(idx*2+1,mid+1,r);
	seg[idx]=min(seg[idx*2],seg[idx*2+1]);
	if(seg[idx]==seg[idx*2]) pos[idx]=pos[idx*2];
	else pos[idx]=pos[idx*2+1];
}
void upd(int idx,int l,int r,int ql,int qr,int x){
	if(ql>qr) return;
	pushdown(idx,l,r);
	if(r<ql or l>qr) return;
	if(ql<=l and r<=qr){
		lazy[idx]+=x;
		pushdown(idx,l,r);
		return;
	}
	int mid=(l+r)/2;
	upd(idx*2,l,mid,ql,qr,x);
	upd(idx*2+1,mid+1,r,ql,qr,x);
	seg[idx]=min(seg[idx*2],seg[idx*2+1]);
	if(seg[idx]==seg[idx*2]) pos[idx]=pos[idx*2];
	else pos[idx]=pos[idx*2+1];
}
pii query(int idx,int l,int r,int ql,int qr){
	if(ql>qr) return {INF,-1};
	pushdown(idx,l,r);
	if(r<ql or l>qr) return {INF,-1};
	if(ql<=l and r<=qr){
		return {seg[idx],pos[idx]};
	}
	int mid=(l+r)/2;
	return min(query(idx*2,l,mid,ql,qr),query(idx*2+1,mid+1,r,ql,qr));
}

void get(int z){
	//cout<<z<<'\n';
	pii mn;
	while(true){
		if(z-k<0){
			mn=min(query(1,0,n-1,0,z-1),query(1,0,n-1,n+(z-k),n-1));
		}
		else{
			mn=query(1,0,n-1,z-k,z-1);
		}
		if(mn.f==0){
			get(mn.s);
		}
		else{
			break;
		}
	}
	ans[z]=cur--;
	if(z-k<0){
		upd(1,0,n-1,0,z-1,-1);
		upd(1,0,n-1,n+(z-k),n-1,-1);
	}
	else{
		upd(1,0,n-1,z-k,z-1,-1);
	}
	upd(1,0,n-1,z,z,INF);
}
vector<vector<int>> nxti,nxtd;
void init(int K, std::vector<int> r) {
	k=K;
	--k;
	n=sz(r);
	REP(i,n){
		arr[i]=r[i];
	}
	cur=n;
	build(1,0,n-1);
	while(cur>0){
		int z=query(1,0,n-1,0,n-1).s;
		assert(query(1,0,n-1,0,n-1).f==0);
		get(z);
	}
	REP(i,n) ans[i+n]=ans[i];
	//REP(i,n) cout<<ans[i]<<' ';
	//cout<<'\n';
	set<pii> s;
	nxti.assign(2*n,vector<int>(20,-1));
	nxtd.assign(2*n,vector<int>(20,-1));
	for(int i=2*n-1;i>=0;i--){
		auto it=s.lower_bound({ans[i],i});
		nxti[i][0]=(it==s.end())?-1:(it->s);
		nxtd[i][0]=(it==s.begin())?-1:(prev(it)->s);
		//cout<<i<<' '<<nxti[i][0]<<' '<<nxtd[i][0]<<'\n';
		s.insert({ans[i],i});
		if(i+k<2*n){
			s.erase({ans[i+k],i+k});
		}
	}
	REP1(j,19){
		REP(i,2*n){
			if(nxti[i][j-1]!=-1){
				nxti[i][j]=nxti[nxti[i][j-1]][j-1];
			}
			else nxti[i][j]=-1;
			if(nxtd[i][j-1]!=-1){
				nxtd[i][j]=nxtd[nxtd[i][j-1]][j-1];
			}
			else nxtd[i][j]=-1;
		}
	}
}
bool ok(int x,int y,int t){
	auto &nxt=(t?nxtd:nxti);
	for(int j=19;j>=0;j--){
		if(nxt[x][j]!=-1 and y-nxt[x][j]>k){
			x=nxt[x][j];
		}
	}
	x=nxt[x][0];
	return (x!=-1 and y-x<=k and (t?ans[x]>=ans[y]:ans[x]<=ans[y]));
}
int compare_plants(int x, int y) {
	bool sam=(y-x<=k);
	if(ans[x]<ans[y]){
		sam|=ok(x,y,0);
		sam|=ok(y,x+n,1);
	}
	else{
		sam|=ok(x,y,1);
		sam|=ok(y,x+n,0);
	}
	if(!sam){
		return 0;
	}
	if(ans[x]>ans[y]) return 1;
	return -1;
} 

• Subtask 1: 5 / 5
• Subtask 2: 14 / 14
• Subtask 3: 13 / 13
• Subtask 4: 17 / 17
• Subtask 5: 11 / 11
• Subtask 6: 15 / 15
• Subtask 7: 25 / 25