Submission #1076954

#	Time	Username	Problem	Language	Result	Execution time	Memory
1076954		andrei_iorgulescu	Tortoise (CEOI21_tortoise)	C++14	18 / 100	989 ms	500 KiB

tortoise

#include <bits/stdc++.h>
#define all(x) (x).begin(),(x).end()
using namespace std;

//#ifndef DLOCAL
//   #define cin fin
//   #define cout fout
//   ifstream cin(".in");
//   ofstream cout(".out");
//#endif

using ll = long long;
using ld = long double;

#define int ll
#define sz(x) ((int)(x).size())

using pii = pair<int,int>;
using tii = tuple<int,int,int>;

const int nmax = 5e5 + 5;

int Ld[nmax], Rd[nmax];
int v[nmax];

bool possible(multiset<int> s)
{
    int last = -1, timer = 0;
    for(auto x : s)
    {
        if(last == -1)
        {
            timer += x - 1;
        }
        else
        {
            if(Ld[last] != Ld[x] || Rd[last] != Rd[x])
                timer += x - last;
            else timer += min(last - Ld[last] + x - Ld[last], Rd[last] - last + Rd[last] - x);
        }
        if(timer > 2 * (x - 1))
        {
            return 0;
        }
        last = x;
        //cerr << timer << '\n';
    }
    //cerr << '\n';
    //for(auto x: s) cerr << x << ' '; cerr << '\n';
    //cerr << "ok\n";
    return 1;
}

signed main()
{
    cin.tie(0) -> sync_with_stdio(0);
    int n;
    cin >> n;

    ll cost = 0;
    for(int i = 1; i <= n; i++)
        cin >> v[i], cost += (v[i] != -1? v[i] : 0);
    for(int lst = -1e9 - 5, i = 1; i <= n; i++)
    {
        if(v[i] == -1) lst = i;
        else Ld[i] = lst;
    }
    for(int lst = 1e9 + 5, i = n; i > 0; i--)
    {
        if(v[i] == -1) lst = i;
        else Rd[i] = lst;
    }

    vector<vector<int>> idxs(n + 1);
    multiset<int> sofar;

    for(int i = 1; i <= n; i++)
    {
        if(v[i] == -1) continue;
        idxs[min(Rd[i] - i, i - Ld[i])].emplace_back(i);
    }

    ll szm = 0;

    srand(time(NULL));
    for(int i = 0; i < 1000; i++)
    {
        for (auto it : sofar)
            v[it]++;
        sofar.clear();
        int itr = 0;
        vector<int> V;
        for(auto &T : idxs)
        {
            for (auto itt : T)
                V.push_back(itt);
            itr++;

            //sort(all(T), greater<int>());
            if (itr % (1 + rand() % 5) == 0)
            {
                shuffle(V.begin(), V.end(), default_random_engine(rand()));
                for(auto x : V)
                {
                    while(v[x] > 0)
                    {
                        sofar.emplace(x);
                        if(possible(sofar)) v[x]--;
                        else
                        {
                            sofar.erase(sofar.find(x));
                            break;
                        }
                    }
                }
                V.clear();
            }

        }
        shuffle(V.begin(), V.end(), default_random_engine(rand()));
        for(auto x : V)
        {
            while(v[x] > 0)
            {
                sofar.emplace(x);
                if(possible(sofar)) v[x]--;
                else
                {
                    sofar.erase(sofar.find(x));
                    break;
                }
            }
        }
        szm = max(szm, (ll)sofar.size());
    }



    cout << cost - szm << '\n';

}

/**
      Töte es durch genaue Untersuchung\Töte es kann es nur noch schlimmer machen\Es lässt es irgendwie atmen
--
*/

• Subtask 1: 8 / 8
• Subtask 2: 10 / 10
• Subtask 3: 0 / 30
• Subtask 4: 0 / 25
• Subtask 5: 0 / 27