Submission #217342

#	Time	Username	Problem	Language	Result	Execution time	Memory
217342		vanic	Cover (COCI18_cover)	C++14	12 / 120	8 ms	768 KiB

cover

#include <iostream>
#include <cstdio>
#include <math.h>
#include <algorithm>
#include <vector>
#include <set>
/*
#include <dora>
#include <vito>
*/
#include <string>
#include <map>
#include <queue>
//#include <>
using namespace std;
typedef long long ll;

const int maxn=5005;
const ll inf=1e18;

int n;
map < pair < int, int >, bool > bio;
vector < pair < int, int > > v;
deque < pair < int, int > > q;
ll dp[maxn];

ll binary(int x){
	int lo=0, hi=x, mid;
	while(lo<hi){
		mid=(lo+hi)/2;
		if(mid){
			if(dp[mid-1]+(ll)v[mid].second*v[x].first<dp[mid]+(ll)v[mid+1].second*v[x].first){
				hi=mid;
			}
			else{
				lo=mid+1;
			}
		}
		else{
			if((ll)v[mid].second*v[x].first<dp[mid]+(ll)v[mid+1].second*v[x].first){
				hi=mid;
			}
			else{
				lo=mid+1;
			}
		}
	}
	if(lo){
		return dp[lo-1]+(ll)v[lo].second*v[x].first;
	}
	else{
		return (ll)v[lo].second*v[x].first;
	}
}


int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	cin >> n;
	pair < int, int > p;
	for(int i=0; i<n; i++){
		cin >> p.first >> p.second;
		p.first=abs(p.first);
		p.second=abs(p.second);
		if(!bio[p]){
			bio[p]=1;
			v.push_back(p);
		}
	}
	n=v.size();
	sort(v.begin(), v.end());
	for(int i=0; i<n; i++){
		while(!q.empty() && q.back().second<=v[i].second){
			q.pop_back();
		}
		q.push_back(v[i]);
	}
	v.clear();
	while(!q.empty()){
		v.push_back(q.front());
		q.pop_front();
	}
	n=v.size();
	for(int i=0; i<n; i++){
		dp[i]=binary(i);
	}
	cout << dp[n-1]*4 << '\n';
	return 0;
}

• Subtask 1: 12 / 120