Submission #302671

#	Time	Username	Problem	Language	Result	Execution time	Memory
302671		junseo	Carnival Tickets (IOI20_tickets)	C++17	100 / 100	1123 ms	72312 KiB

tickets

#include "tickets.h"
#include <bits/stdc++.h>
#define fi first
#define se second
#define eb emplace_back
#define all(v) (v).begin(), (v).end()
#define rmin(r, x) r = min(r, x)
#define rmax(r, x) r = max(r, x)
#define ends ' '
#define endl '\n'
#define fastio ios_base::sync_with_stdio(0), cin.tie(0)
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
 
const int maxn = 1510;
const int maxm = 1510;
const int maxk = maxm;
 
int n, m, k, l[maxn], r[maxn];
ll c[maxn][maxk];
vector<vector<int>> ans;
 
struct Node {
	int i, j;
	Node(int i, int j) : i(i), j(j) {}
};
 
bool operator < (Node l, Node r) {
	if(l.j == k)	return true;
	if(r.j == k)	return false;
	return c[l.i][l.j + 1] - c[l.i][l.j] < c[r.i][r.j + 1] - c[r.i][r.j];
}
 
long long find_maximum(int _k, vector<vector<int>> x) {
	n = x.size();
	m = x[0].size();
	k = _k;
	ans.resize(n);
 
	ll ret = 0;
	priority_queue<Node> pq;
	for(int i = 0; i < n; ++i) {
		ans[i].resize(m, -1);
		l[i] = 0, r[i] = m - 1;
		for(int j = 0; j < k; ++j)		c[i][k] += -x[i][j];
		for(int j = k - 1; j >= 0; --j)	c[i][j] = c[i][j + 1] + x[i][j] + x[i][m - (k - j)];
		pq.push({i, 0});
		ret += c[i][0];
	}
	for(int i = 0; i < n * k / 2; ++i) {
		Node t = pq.top();	pq.pop();
		ret += (c[t.i][t.j + 1] - c[t.i][t.j]);
		pq.push({t.i, t.j + 1});
	}
 
	vector<pii> v;
	while(!pq.empty()) {
		Node t = pq.top();	pq.pop();
		v.eb(t.j, t.i);
	}
	for(int T = 0; T < k; ++T) {
		sort(all(v));
		for(int i = 0; i < n; ++i) {
			int j = v[i].se;
			if(i < n / 2) {
				ans[j][r[j]--] = T;
			}
			else {
				ans[j][l[j]++] = T;
				--v[i].fi;
			}
		}
	}
 
	allocate_tickets(ans);
	return ret;
}

• 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