Submission #982293

# Submission time Handle Problem Language Result Execution time Memory
982293 2024-05-14T06:03:28 Z davitmarg Sequence (APIO23_sequence) C++17
41 / 100
2000 ms 48956 KB
#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <algorithm>
#include <cmath>
#include <vector>
#include <string>
#include <cstring>
#include <map>
#include <unordered_map>
#include <set>
#include <unordered_set>
#include <queue>
#include <bitset>
#include <stack>
#include <cassert>
#include <iterator>
#include <random>
#include <chrono>
#include <fstream>
#define fastIO                   \
    ios::sync_with_stdio(false); \
    cin.tie(0);                  \
    cout.tie(0);
#define mod 1000000007ll
#define LL long long
#define LD long double
#define MP make_pair
#define PB push_back
#define all(v) v.begin(), v.end()
using namespace std;

const int N = 500005;

int n, a[N], ans;
vector<int> pos[N];
pair<int, int> t[N * 4];
int d[N * 4];

pair<int, int> merge(pair<int, int> a, pair<int, int> b)
{
    return MP(min(a.first, b.first), max(a.second, b.second));
}

void push(int v, int l, int r)
{
    if (d[v] == 0)
        return;
    if (l != r)
    {
        d[v * 2] += d[v];
        d[v * 2 + 1] += d[v];
    }
    t[v] = MP(t[v].first + d[v], t[v].second + d[v]);
    d[v] = 0;
}

void add(int v, int l, int r, int i, int j, int val)
{
    push(v, l, r);
    if (i > j)
        return;
    if (i == l && j == r)
    {
        d[v] += val;
        push(v, l, r);
        return;
    }

    int m = (l + r) / 2;
    add(v * 2, l, m, i, min(m, j), val);
    add(v * 2 + 1, m + 1, r, max(m + 1, i), j, val);
    t[v] = merge(t[v * 2], t[v * 2 + 1]);
}

pair<int, int> get(int v, int l, int r, int i, int j)
{
    push(v, l, r);
    if (i > j)
        return MP(mod, -mod);
    if (i == l && j == r)
        return t[v];

    int m = (l + r) / 2;
    return merge(
        get(v * 2, l, m, i, min(m, j)),
        get(v * 2 + 1, m + 1, r, max(m + 1, i), j)
    );
}




int sequence(int nn, vector<int> aa)
{
    n = nn;
    for (int i = 1; i <= n; i++)
        a[i] = aa[i - 1];


    for (int i = 1; i <= n; i++)
        pos[a[i]].push_back(i);

    for (int i = 1; i <= n; i++)
        add(1, 0, n, i, n, 1);


    for (int x = 1; x <= n; x++)
    {
        for (int p = 0; p < pos[x].size(); p++)
        {
            int i = pos[x][p];

            int l = 0;
            int r = p;
            
            while (l <= r)
            {
                int m = (l + r) / 2;

                int j = pos[x][m];
                int len = p - m + 1;

                pair<int, int> dr = get(1, 0, n, i, n);
                dr.first -= len;
                dr.second -= len;
                pair<int, int> dl = get(1, 0, n, 0, j - 1);
                pair<int, int> d = MP(dr.first - dl.second, dr.second - dl.first);


                if ((d.second < 0 && len >= -d.second) || (d.first > 0 && len >= d.first) || (d.first <= 0 && d.second >= 0))
                {
                    ans = max(ans, len);
                    r = m - 1;
                }
                else
                    l = m + 1;
            }

        }

        for (int p = 0; p < pos[x].size(); p++)
        {
            int i = pos[x][p];
            add(1, 0, n, i, n, -1);
        }


        for (int p = 0; p < pos[x].size(); p++)
        {
            int i = pos[x][p];
            add(1, 0, n, i, n, -1);
        }


        for (int p = 0; p < pos[x].size(); p++)
        {
            int i = pos[x][p];
            for (int k = p; k >= 0; k--)
            {
                int j = pos[x][k];
                int len = p - k + 1;

                pair<int, int> dr = get(1, 0, n, i, n);
                dr.first += len;
                dr.second += len;
                pair<int, int> dl = get(1, 0, n, 0, j - 1);
                pair<int, int> d = MP(dr.first - dl.second, dr.second - dl.first);


                if ((d.second < 0 && len >= -d.second) || (d.first > 0 && len >= d.first) || (d.first <= 0 && d.second >= 0))
                    ans = max(ans, len);
            }
        }
    }


    return ans;
}

#ifdef death



void solve()
{
    int nn;
    vector<int> aa;
    cin >> nn;
    for (int i = 0; i < nn; i++)
    {
        int x;
        cin >> x;
        aa.push_back(x);
    }

    cout << sequence(nn, aa) << endl;
}

int main()
{
    fastIO;
    int T = 1;
    //cin >> T;
    while (T--)
        solve();
    return 0;
}
#endif // death

/*

7
1 2 3 1 2 1 3

9
1 1 2 3 4 3 2 1 1

14
2 6 2 5 3 4 2 1 4 3 5 6 3 2

*/

Compilation message

sequence.cpp: In function 'int sequence(int, std::vector<int>)':
sequence.cpp:109:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  109 |         for (int p = 0; p < pos[x].size(); p++)
      |                         ~~^~~~~~~~~~~~~~~
sequence.cpp:141:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  141 |         for (int p = 0; p < pos[x].size(); p++)
      |                         ~~^~~~~~~~~~~~~~~
sequence.cpp:148:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  148 |         for (int p = 0; p < pos[x].size(); p++)
      |                         ~~^~~~~~~~~~~~~~~
sequence.cpp:155:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  155 |         for (int p = 0; p < pos[x].size(); p++)
      |                         ~~^~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 3 ms 16732 KB Output is correct
2 Correct 3 ms 16732 KB Output is correct
3 Correct 3 ms 16732 KB Output is correct
4 Correct 4 ms 16732 KB Output is correct
5 Correct 3 ms 16732 KB Output is correct
6 Correct 4 ms 16732 KB Output is correct
7 Correct 4 ms 16732 KB Output is correct
8 Correct 3 ms 16732 KB Output is correct
9 Correct 4 ms 16732 KB Output is correct
10 Correct 3 ms 16732 KB Output is correct
11 Correct 4 ms 16732 KB Output is correct
12 Correct 3 ms 16732 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 16732 KB Output is correct
2 Correct 3 ms 16732 KB Output is correct
3 Correct 3 ms 16732 KB Output is correct
4 Correct 4 ms 16732 KB Output is correct
5 Correct 3 ms 16732 KB Output is correct
6 Correct 4 ms 16732 KB Output is correct
7 Correct 4 ms 16732 KB Output is correct
8 Correct 3 ms 16732 KB Output is correct
9 Correct 4 ms 16732 KB Output is correct
10 Correct 3 ms 16732 KB Output is correct
11 Correct 4 ms 16732 KB Output is correct
12 Correct 3 ms 16732 KB Output is correct
13 Correct 7 ms 16732 KB Output is correct
14 Correct 6 ms 16732 KB Output is correct
15 Correct 18 ms 16904 KB Output is correct
16 Correct 17 ms 16732 KB Output is correct
17 Correct 98 ms 16888 KB Output is correct
18 Correct 5 ms 16728 KB Output is correct
19 Correct 13 ms 16780 KB Output is correct
20 Correct 23 ms 16728 KB Output is correct
21 Correct 17 ms 16732 KB Output is correct
22 Correct 15 ms 16732 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 16732 KB Output is correct
2 Correct 883 ms 43348 KB Output is correct
3 Correct 908 ms 43348 KB Output is correct
4 Execution timed out 2065 ms 35292 KB Time limit exceeded
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 3 ms 16732 KB Output is correct
2 Execution timed out 2020 ms 35324 KB Time limit exceeded
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 970 ms 48852 KB Output is correct
2 Correct 1018 ms 48956 KB Output is correct
3 Correct 1002 ms 48396 KB Output is correct
4 Correct 1029 ms 48400 KB Output is correct
5 Correct 992 ms 45060 KB Output is correct
6 Correct 982 ms 44836 KB Output is correct
7 Correct 943 ms 43856 KB Output is correct
8 Correct 899 ms 43548 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 16732 KB Output is correct
2 Correct 3 ms 16732 KB Output is correct
3 Correct 3 ms 16732 KB Output is correct
4 Correct 4 ms 16732 KB Output is correct
5 Correct 3 ms 16732 KB Output is correct
6 Correct 4 ms 16732 KB Output is correct
7 Correct 4 ms 16732 KB Output is correct
8 Correct 3 ms 16732 KB Output is correct
9 Correct 4 ms 16732 KB Output is correct
10 Correct 3 ms 16732 KB Output is correct
11 Correct 4 ms 16732 KB Output is correct
12 Correct 3 ms 16732 KB Output is correct
13 Correct 7 ms 16732 KB Output is correct
14 Correct 6 ms 16732 KB Output is correct
15 Correct 18 ms 16904 KB Output is correct
16 Correct 17 ms 16732 KB Output is correct
17 Correct 98 ms 16888 KB Output is correct
18 Correct 5 ms 16728 KB Output is correct
19 Correct 13 ms 16780 KB Output is correct
20 Correct 23 ms 16728 KB Output is correct
21 Correct 17 ms 16732 KB Output is correct
22 Correct 15 ms 16732 KB Output is correct
23 Correct 164 ms 22108 KB Output is correct
24 Correct 185 ms 22144 KB Output is correct
25 Correct 167 ms 22152 KB Output is correct
26 Execution timed out 2045 ms 21072 KB Time limit exceeded
27 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 3 ms 16732 KB Output is correct
2 Correct 3 ms 16732 KB Output is correct
3 Correct 3 ms 16732 KB Output is correct
4 Correct 4 ms 16732 KB Output is correct
5 Correct 3 ms 16732 KB Output is correct
6 Correct 4 ms 16732 KB Output is correct
7 Correct 4 ms 16732 KB Output is correct
8 Correct 3 ms 16732 KB Output is correct
9 Correct 4 ms 16732 KB Output is correct
10 Correct 3 ms 16732 KB Output is correct
11 Correct 4 ms 16732 KB Output is correct
12 Correct 3 ms 16732 KB Output is correct
13 Correct 7 ms 16732 KB Output is correct
14 Correct 6 ms 16732 KB Output is correct
15 Correct 18 ms 16904 KB Output is correct
16 Correct 17 ms 16732 KB Output is correct
17 Correct 98 ms 16888 KB Output is correct
18 Correct 5 ms 16728 KB Output is correct
19 Correct 13 ms 16780 KB Output is correct
20 Correct 23 ms 16728 KB Output is correct
21 Correct 17 ms 16732 KB Output is correct
22 Correct 15 ms 16732 KB Output is correct
23 Correct 883 ms 43348 KB Output is correct
24 Correct 908 ms 43348 KB Output is correct
25 Execution timed out 2065 ms 35292 KB Time limit exceeded
26 Halted 0 ms 0 KB -