Submission #428396

#	Time	Username	Problem	Language	Result	Execution time	Memory
428396		egekabas	Carnival Tickets (IOI20_tickets)	C++14	100 / 100	950 ms	57448 KiB

tickets

#include "tickets.h"
#include <bits/stdc++.h>
#define all(x) (x).begin(), (x).end()
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pull;
typedef pair<int, int> pii;
typedef pair<ld, ld> pld;

long long find_maximum(int k, vector<vector<int>> x) {
	int n = x.size();
	int m = x[0].size();
	vector<int> beg(n), fin(n);
	for(int i = 0; i < n; ++i){
		beg[i] = k-1;
		fin[i] = m-1;
	}
	set<pii, greater<pii>> s;
	for(int i = 0; i < n; ++i)
		s.insert({x[i][beg[i]]+x[i][fin[i]], i});
	for(int i = 0; i < n*k/2; ++i){
		int idx = s.begin()->ss;
		s.erase(s.begin());
		//cout << idx << ' ' << ' ' << beg[idx] << ' ' << fin[idx] << '\n';
		--fin[idx];
		--beg[idx];
		if(beg[idx] >= 0)
			s.insert({x[idx][beg[idx]]+x[idx][fin[idx]], idx});
	}
	ll ans = 0;
	for(int i = 0; i < n; ++i){
		++fin[i];
		for(int j = 0; j <= beg[i]; ++j)
			ans -= x[i][j];
		for(int j = fin[i]; j < m; ++j)
			ans += x[i][j];
	}

	vector<vector<int>> ret(n, vector<int>(m, -1));
	for(int round = 0; round < k; ++round){
		int curbig = 0;
		for(int i = 0; i < n; ++i)
			if(beg[i] < 0){
				ret[i][fin[i]] = round;
				++fin[i];
				++curbig;
			}
		for(int i = 0; i < n; ++i)
			if(beg[i] >= 0){
				if(curbig < n/2 && fin[i] < m){
					ret[i][fin[i]] = round;
					++fin[i];
					++curbig;
				}
				else{
					ret[i][beg[i]] = round;
					--beg[i];
				}
			}
	}

	
	allocate_tickets(ret);
	return ans;
}

• Subtask 1: 11 / 11
• Subtask 2: 16 / 16
• Subtask 3: 14 / 14
• Subtask 4: 14 / 14
• Subtask 5: 12 / 12
• Subtask 6: 23 / 23
• Subtask 7: 10 / 10