Submission #565915

#	Time	Username	Problem	Language	Result	Execution time	Memory
565915		sidon	Carnival Tickets (IOI20_tickets)	C++17	100 / 100	809 ms	147208 KiB

tickets

#include "tickets.h"
#include "bits/stdc++.h"
using namespace std;
using ll = long long;

ll find_maximum(int k, vector<vector<int>> x) {
	int n = x.size(), m = x[0].size();
	vector<vector<int>> g(n, vector<int> (m, -1));
	ll res {};

	vector<array<ll, 3>> a;
	int b[n];

	for(int i = n; i--; ) {
		b[i] = k;
		ll cur {};
		for(int j = 0; j < k; ++j)
			cur -= x[i][j];
		res += cur;

		for(int j = k; j--; ) {
			ll add = x[i][j] + x[i][m+j-k];
			a.push_back({add, i, j});
			cur += add;
		}
	}

	sort(rbegin(a), rend(a));

	for(int i = (k * n / 2); i--; ) {
		res += a[i][0];
		b[a[i][1]] = min((ll)b[a[i][1]], a[i][2]);
	}

	for(int i = n; i--; ) {
		for(int j = b[i]; j--; )
			--g[i][j];
		for(int j = 0; j < k - b[i]; ++j)
			++g[i][m-1-j];
	}

	int l[n] {}, r[n];
	bool vis[n];
	fill(r, r + n, m-1);

	for(int c = 0; c < k; ++c) {
		int cnt {};
		fill(vis, vis + n, 0);
		for(int i = n; i--; ) {
			if(g[i][l[i]] > -2)
				g[i][r[i]--] = c, ++cnt, vis[i] = 1;
			else if(g[i][r[i]] < 0)
				g[i][l[i]++] = c, --cnt, vis[i] = 1;
		}
		for(int i = n; i--; ) if(!vis[i]) {
			if(cnt < 0)
				g[i][r[i]--] = c, ++cnt;
			else
				g[i][l[i]++] = c, --cnt;
		}
	}

	return allocate_tickets(g), res;
}

• 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