Submission #340063

#	Time	Username	Problem	Language	Result	Execution time	Memory
340063		Sprdalo	Longest beautiful sequence (IZhO17_subsequence)	C++17	23 / 100	153 ms	18380 KiB

subsequence

#include <bits/stdc++.h>

using namespace std;

#define int ll
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<double> vd;
typedef vector<bool> vb;
typedef vector<char> vc;
typedef vector<string> vs;
typedef vector<pi> vp;
typedef vector<pl> vpl;

const int maxn = 1e5 + 10;
vi t[maxn], cnt(256,0);

void init(vi a, vi k){
    int n = k.size();

    for (int i = 0; i < n; ++i){
        int x = a[i];

        for (int y = 0; y < 256; ++y){
            if (cnt[y] != -1 && __builtin_popcount((y&a[i])) == k[i])
                t[i].push_back(y);
        }
    }
}

signed main()
{
    ios_base::sync_with_stdio(false); 
    cin.tie(nullptr); 
    cout.tie(nullptr); 
    cerr.tie(nullptr);    

    int n;
    cin >> n;

    vi a(n);
    for (auto& i : a)
        cin >> i;

    vi k(n);
    for (auto& i : k)
        cin >> i;

    if (n <= 5000){
        vi d(n), last(n, -1);
        for (int i = 0; i < n; ++i){
            d[i] = 1;

            for (int j = 0; j < i; ++j){
                if (d[j]+1 > d[i] && __builtin_popcount(a[i]&a[j]) == k[i]){
                    d[i] = d[j]+1;
                    last[i] = j;
                }   
            }
        }

        int ind = max_element(d.begin(), d.end()) - d.begin();
        cout << d[ind] << '\n';

        vi sol;
        while(ind != -1){
            sol.push_back(ind+1);
            ind = last[ind];
        }

        reverse(sol.begin(), sol.end());

        for (auto& i : sol)
            cout << i << ' ';
        cout << '\n';
        return 0;
    }

    init(a,k);

    vi d(n), pos(256, -1), last(n, -1);
    for (int i = 0; i < n; ++i){
        d[i] = 1;

        for (int x : t[i]){
            if (pos[x] != -1 && d[i] < d[pos[x]]+1){
                d[i] = d[pos[x]]+1;
                last[i] = pos[x];
            }
        }

        pos[a[i]] = i;
    }

    int ind = max_element(d.begin(), d.end())-d.begin();
    vi sol;
    while(ind != -1){
        sol.push_back(ind);

        ind = last[ind];
    }

    reverse(sol.begin(), sol.end());
    cout << (int)sol.size() << '\n';
    for (auto& i : sol)
        cout << i+1 << ' ';
}

Compilation message (stderr)

subsequence.cpp: In function 'void init(vi, vi)':
subsequence.cpp:26:13: warning: unused variable 'x' [-Wunused-variable]
   26 |         int x = a[i];
      |             ^

• Subtask 1: 7 / 7
• Subtask 2: 16 / 16
• Subtask 3: 0 / 17
• Subtask 4: 0 / 60