Submission #1053991

#	Time	Username	Problem	Language	Result	Execution time	Memory
1053991		pcc	Comparing Plants (IOI20_plants)	C++17	14 / 100	4069 ms	161364 KiB

plants

#include "plants.h"
#include <bits/stdc++.h>
using namespace std;

#define pii pair<int,int>
#define fs first
#define sc second

const int B = 20;
const int mxn = 4e5+10;

int arr[mxn];
int N;
int K;
int perm[mxn];
int dp[mxn];
set<int> st;
set<pii> rng;

struct SEG{
#define ls now*2+1
#define rs now*2+2
#define mid ((l+r)>>1)
	pii seg[mxn*4];
	void modify(int now,int l,int r,int s,int e,int v){
		if(l>=s&&e>=r){
			seg[now].sc += v;
			return;
		}
		if(mid>=s)modify(ls,l,mid,s,e,v);
		if(mid<e)modify(rs,mid+1,r,s,e,v);
		seg[now].fs = min(seg[ls].fs+seg[ls].sc,seg[rs].fs+seg[rs].sc);
		return;
	}
	int get_mn(int now,int l,int r){
		if(l == r){
			return l;
		}
		if(seg[ls].fs+seg[ls].sc<seg[rs].fs+seg[rs].sc)return get_mn(ls,l,mid);
		else return get_mn(rs,mid+1,r);
	}
#undef ls
#undef rs
#undef mid
}seg;


void add(int p){
	int nxt = *st.upper_bound(p);
	int pre = *(--st.upper_bound(p));
	rng.erase(pii(nxt-pre,nxt));
	rng.insert(pii(nxt-p,nxt));
	rng.insert(pii(p-pre,p));
	st.insert(p);
	return;
}

void del(int p){
	auto it = st.find(p);
	int pre = *prev(it),nxt = *next(it);
	rng.erase(pii(p-pre,p));
	rng.erase(pii(nxt-p,nxt));
	rng.insert(pii(nxt-pre,nxt));
	st.erase(p);
	return;
}

struct DB{
	int dp[mxn][B];
	DB(){
		memset(dp,-1,sizeof(dp));
	}
	void build(int s,int e){
		if(e<s){
			for(int i = s;i>=e;i--){
				for(int j = 1;j<B;j++){
					int pre = dp[i][j-1];
					if(pre == -1)continue;
					dp[i][j] = dp[pre][j-1];
				}
			}
		}
		else{
			for(int i = s;i<=e;i++){
				for(int j = 1;j<B;j++){
					int pre = dp[i][j-1];
					if(pre == -1)continue;
					dp[i][j] = dp[pre][j-1];
				}
			}
		}
	}
};

DB lmx,rmx,lmn,rmn;

void calc(int id){
	auto it = rng.rbegin();
	if(it->sc >= N*2)it++;
	auto pos = it->sc;
	pos %= N;
	//cerr<<id<<":"<<pos<<','<<it->fs<<endl;
	assert(it->fs>=K);
	del(pos);
	del(pos+N);
	perm[pos] = id;
	seg.modify(0,0,N*2-1,pos+N-K+1,pos+N,-1);
	seg.modify(0,0,N*2-1,max(pos-K+1,0),pos,-1);
	if(pos-K+1<0)seg.modify(0,0,N*2-1,N*2-1+(pos-K+1)+1,N*2-1,-1);
	while(seg.seg[0].fs+seg.seg[0].sc == 0){
		int p = seg.get_mn(0,0,N*2-1);
		p %= N;
		add(p);
		seg.modify(0,0,N*2-1,p,p,mxn*4);
		add(p+N);
		seg.modify(0,0,N*2-1,p+N,p+N,mxn*4);
	}
	return;
}

void init(int k, std::vector<int> r) {
	K = k;
	N = r.size();
	for(int i = 0;i<N;i++)arr[i] = arr[i+N] = r[i];
	st.insert(-1);
	st.insert(N*2);
	rng.insert(pii(N*2+1,N*2));
	for(int i = 0;i<N*2;i++){
		if(!arr[i]){
			add(i);
		}
		if(arr[i])seg.modify(0,0,N*2-1,i,i,arr[i]);
		else seg.modify(0,0,N*2-1,i,i,mxn*4);
	}
	//cerr<<"INIT!: "<<rng.rbegin()->fs<<endl;
	//for(auto &i:rng)cerr<<i.fs<<','<<i.sc<<endl;
	for(int i = N-1;i>=0;i--)calc(i);
	//for(int i = 0;i<N;i++)cerr<<perm[i]<<',';cerr<<endl;
	for(int i = N;i<N*2;i++)perm[i] = perm[i-N];
	set<pii> st;
	for(int i = 0;i<K-1;i++){
		auto it = st.lower_bound(pii(perm[i],-1));
		if(it != st.end())lmx.dp[i][0] = it->sc;
		if(it != st.begin()){
			it--;
			lmn.dp[i][0] = it->sc;
		}
		st.insert(pii(perm[i],i));
	}
	for(int i = K-1;i<N*2;i++){
		auto it = st.lower_bound(pii(perm[i],-1));
		if(it != st.end())lmx.dp[i][0] = it->sc;
		if(it != st.begin()){
			it--;
			lmn.dp[i][0] = it->sc;
		}
		st.erase(pii(perm[i-K+1],i-K+1));
		st.insert(pii(perm[i],i));
	}
	st.clear();
	for(int i = 0;i<K-1;i++){
		auto it = st.lower_bound(pii(perm[N*2-1-i],-1));
		if(it != st.end())rmx.dp[i][0] = it->sc;
		if(it != st.begin()){
			it--;
			rmn.dp[N*2-1-i][0] = it->sc;
		}
		st.insert(pii(perm[N*2-1-i],N*2-1-i));
	}
	for(int i = K-1;i<N*2;i++){
		auto it = st.lower_bound(pii(perm[N*2-1-i],-1));
		if(it != st.end())rmx.dp[i][0] = it->sc;
		if(it != st.begin()){
			it--;
			rmn.dp[N*2-1-i][0] = it->sc;
		}
		st.erase(pii(perm[N*2-1-i+K-1],N*2-1-i+K-1));
		st.insert(pii(perm[N*2-1-i],N*2-1-i));
	}
	rmn.build(N*2-1,0);
	rmx.build(N*2-1,0);
	lmn.build(0,N*2-1);
	lmx.build(0,N*2-1);
	/*
	cerr<<"PERM: "<<endl;for(int i = 0;i<N*2;i++)cerr<<perm[i]<<' ';cerr<<endl;
	cerr<<"LMX: "<<endl;for(int i = 0;i<N*2;i++)cerr<<lmx.dp[i][0]<<' ';cerr<<endl;
	cerr<<"LMN: "<<endl;for(int i = 0;i<N*2;i++)cerr<<lmn.dp[i][0]<<' ';cerr<<endl;
	cerr<<"RMX: "<<endl;for(int i = 0;i<N*2;i++)cerr<<rmx.dp[i][0]<<' ';cerr<<endl;
	cerr<<"RMN: "<<endl;for(int i = 0;i<N*2;i++)cerr<<rmn.dp[i][0]<<' ';cerr<<endl;
	*/
	return;
}

int compare_plants(int x, int y) {

	int ans = 0;

	int s = x,e = y;
	if(e<s)e += N;
	while(e-s>=K){
		if(rmx.dp[s][0] != -1&&rmx.dp[s][0]<e)s = rmx.dp[s][0];
		else break;
	}
	if(e-s<K&&perm[e]>perm[s])ans = -1;
	s = x,e = y;
	if(e>s)s += N;
	while(s-e>=K){
		if(lmx.dp[s][0] != -1&&lmx.dp[s][0]>e)s = lmx.dp[s][0];
		else break;
	}
	if(s-e<K&&perm[e]>perm[s])ans = -1;

	s = x,e = y;
	if(e<s)e += N;
	while(e-s>=K){
		if(rmn.dp[s][0] != -1&&rmn.dp[s][0]<e)s = rmn.dp[s][0];
		else break;
	}
	if(e-s<K&&perm[e]<perm[s])ans = 1;
	s = x,e = y;
	if(e>s)s += N;
	while(s-e>=K){
		if(lmn.dp[s][0] != -1&&lmn.dp[s][0]>e)s = lmn.dp[s][0];
		else break;
	}
	if(s-e<K&&perm[e]<perm[s])ans = 1;
	/*
	for(int i = B-1;i>=0;i--){
		if(e-s<K)break;
		if(rmx.dp[s][i] != -1&&rmx.dp[s][i]<e)s = rmx.dp[s][i];
	}
	if(e-s<K&&perm[e]>perm[s])ans = -1;
	s = x,e = y;
	if(e>s)s += N;
	for(int i = B-1;i>=0;i--){
		if(s-e<K)break;
		if(lmx.dp[s][i] != -1&&lmx.dp[s][i]>e)s = lmx.dp[s][i];
	}
	if(s-e<K&&perm[e]>perm[s])ans = -1;

	s = x,e = y;
	if(e<s)e += N;
	for(int i = B-1;i>=0;i--){
		if(e-s<K)break;
		if(rmn.dp[s][i] != -1&&rmn.dp[s][i]<e)s = rmn.dp[s][i];
	}
	if(e-s<K&&perm[e]<perm[s])ans = 1;
	s = x,e = y;
	if(e>s)s += N;
	for(int i = B-1;i>=0;i--){
		if(s-e<K)break;
		if(lmn.dp[s][i] != -1&&lmn.dp[s][i]>e)s = lmn.dp[s][i];
	}
	if(s-e<K&&perm[e]<perm[s])ans = 1;
	*/
	return ans;
}

• Subtask 1: 0 / 5
• Subtask 2: 14 / 14
• Subtask 3: 0 / 13
• Subtask 4: 0 / 17
• Subtask 5: 0 / 11
• Subtask 6: 0 / 15
• Subtask 7: 0 / 25