Submission #576222

#	Time	Username	Problem	Language	Result	Execution time	Memory
576222		SlavicG	Carnival Tickets (IOI20_tickets)	C++17	41 / 100	681 ms	68332 KiB

tickets

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

#define ll long long
#define sz(a) (int)a.size()
#define pb push_back
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()
#define forn(i, n) for(int i=0;i < n; ++i)

ll calc(vector<int> v) {
    sort(all(v));
    int n  = sz(v);
    int mid = v[n / 2];
    ll ans = 0;
    for(int i = 0; i < n; ++i) ans += abs(v[i] - mid);
    return ans;
}

long long find_maximum(int k, std::vector<std::vector<int>> x) {
	int n = x.size();
	int m = x[0].size();
	std::vector<std::vector<int>> answer(n, vector<int>(m, -1));

	if(m == 1) {
        answer.assign(n, vector<int>(m, 0));
        vector<ll> a;
        forn(i, n) a.pb(x[i][0]);
        sort(all(a));
        ll ans = 0;
        forn(i, n) ans += abs(a[i] - a[n / 2]);
        allocate_tickets(answer);
        return ans;
	}

    if(k == 1) {
        vector<int> v;
        vector<int> mn(n, 0), mx(n, 0);
        vector<pair<int, int>> amogus;
        for(int i = 0; i < n; ++i) {
            for(int j = 0; j < m; ++j) {
                if(mn[i] > x[i][j]) mn[i] = j;
                if(mx[i] < x[i][j]) mx[i] = j;
            }
            amogus.pb({x[i][mn[i]] + x[i][mx[i]], i});
        }

        sort(all(amogus));

        for(int i = 0; i < n; ++i) {
            int j = amogus[i].second;
            if(i < n / 2) {
                v.pb(x[j][mn[j]]);
                answer[j][mn[j]] = 0;
            } else {
                v.pb(x[j][mx[j]]);
                answer[j][mx[j]] = 0;
            }
        }
        ll ans = calc(v);
        allocate_tickets(answer);
        return ans;

    }

	vector<int> zeroes[n], ones[n];
	for(int i = 0; i < n; ++i) {
        for(int j = 0; j < m; ++j) {
            if(x[i][j] == 0) zeroes[i].pb(j);
            else ones[i].pb(j);
        }
	}

    priority_queue<pair<int, int>> q;
    for(int i = 0; i < n; ++i) {
        if(sz(zeroes[i])) q.push({sz(zeroes[i]), i});
    }

    ll ans = 0;
    for(int kk = 0; kk < k; ++kk) {
        int cnt = 0;
        vector<int> v;
        vector<bool> vis(n, false);
        while(cnt < n / 2 && sz(q)) {
            answer[q.top().second][zeroes[q.top().second].back()] = kk;
            zeroes[q.top().second].pop_back();
            assert(vis[q.top().second] == false);
            vis[q.top().second] = true;
            q.pop();
            ++cnt;
            v.pb(0);
        }
        for(int i = 0; i < n && cnt < n; ++i) {
            if(sz(ones[i]) && !vis[i]) {
                v.pb(1);
                ++cnt;
                answer[i][ones[i].back()] = kk;
                ones[i].pop_back();
                vis[i] = true;
            }
        }
        for(int i = 0; i < n && cnt < n; ++i) {
            if(!vis[i]) {
                assert(sz(zeroes[i]));
                v.pb(0);
                answer[i][zeroes[i].back()] = kk;
                zeroes[i].pop_back();
                ++cnt;
                vis[i] = true;
            }
        }

        while(sz(q)) q.pop();
        for(int i = 0; i < n; ++i) {
            if(sz(zeroes[i])) {
                q.push({sz(zeroes[i]), i});
            }
        }
        assert(sz(v) == n);
        ans += calc(v);
    }

    allocate_tickets(answer);
	return ans;
}

• Subtask 1: 11 / 11
• Subtask 2: 16 / 16
• Subtask 3: 14 / 14
• Subtask 4: 0 / 14
• Subtask 5: 0 / 12
• Subtask 6: 0 / 23
• Subtask 7: 0 / 10