oj.uz

Submission #946359

# Submission time Handle Problem Language Result Execution time Memory
946359 2024-03-14T14:24:26 Z Nhoksocqt1 Sequence (APIO23_sequence) C++17
35 / 100
 220 ms 11472 KB 
#ifndef Nhoksocqt1
    #include "sequence.h"
#endif // Nhoksocqt1
#include<bits/stdc++.h>
using namespace std;

#define inf 0x3f3f3f3f
#define sz(x) int((x).size())
#define fi first
#define se second
typedef long long ll;
typedef pair<int, int> ii;

template<class X, class Y>
	inline bool maximize(X &x, const Y &y) {return (x < y ? x = y, 1 : 0);}
template<class X, class Y>
	inline bool minimize(X &x, const Y &y) {return (x > y ? x = y, 1 : 0);}

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int Random(int l, int r) {
    return uniform_int_distribution<int>(l, r)(rng);
}

const int MAXN = 500005;

int val[MAXN], cnt[MAXN], nArr;

int sub2(void) {
    int res(1);
    for (int l = 1; l <= nArr; ++l) {
        set<int> Set;
        int pos(val[l]), cntPos(1);
        Set.insert(pos);
        ++cnt[pos];

        for (int r = l + 1; r <= nArr; ++r) {
            cntPos += (val[r] <= pos);
            if(++cnt[val[r]] == 1)
                Set.insert(val[r]);

            while(cntPos < (r - l + 1) / 2 + 1) {
                auto it = Set.lower_bound(pos); ++it;
                assert(it != Set.end());
                pos = *it;
                cntPos += cnt[pos];
            }

            while(cntPos - cnt[pos] >= (r - l + 1) / 2 + 1) {
                cntPos -= cnt[pos];
                auto it = Set.lower_bound(pos);
                assert(it != Set.begin()); --it;
                pos = *it;
            }

            //cout << l << ' ' << r << ' ' << pos << ' ' << cntPos << '\n';
            res = max(res, cnt[pos]);
            if((r - l + 1) % 2 == 0 && cntPos - cnt[pos] >= (r - l + 1) / 2) {
                auto it = Set.lower_bound(pos);
                assert(it != Set.begin()); --it;
                res = max(res, cnt[*it]);
            }
        }

        for (int r = l; r <= nArr; ++r)
            --cnt[val[r]];
    }

    return res;
}

int sub3(void) {
    int res(0);
    for (int i = 1; i <= nArr; ) {
        int j(i);
        while(j <= nArr && val[j] == val[i])
            ++j;

        res = max(res, j - i);
        i = j;
    }

    for (int i = 1; i <= nArr; ++i)
        ++cnt[val[i]];

    int j(nArr);
    for (int i = 1; i <= j; ++i) {
        if(i > 1 && val[i] == val[i - 1])
            continue;

        while(j > i && val[j] < val[i])
            --cnt[val[j--]];

        if(j > i && val[i] == val[j]) {
            int cntPos = cnt[val[i]];
            if(cnt[val[i]] + i - 1 + nArr - j >= (nArr + 1) / 2)
                res = max(res, cnt[val[i]]);
        }
    }

    return res;
}

int sequence(int _N, vector<int> _A) {
    nArr = _N;
    for (int i = 1; i <= nArr; ++i)
        val[i] = _A[i - 1];

    bool check3(1);
    for (int i = 1; i <= nArr; ++i) {
        check3 &= (i <= 2 || val[i - 2] <= val[i - 1] || val[i - 2] >= val[i - 1] && val[i - 1] >= val[i]);
    }

    if(nArr <= 2000) {
        return sub2();
    } else
        if(check3) {
            return sub3();
        }
}

#ifdef Nhoksocqt1

int main(void) {
    ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);

    #define TASK "sequence"
    if(fopen(TASK".inp", "r")) {
        freopen(TASK".inp", "r", stdin);
        freopen(TASK".out", "w", stdout);
    }

    vector<int> _A;
    int _N;
    cin >> _N;

    _A.resize(_N);
    for (int i = 0; i < _N; ++i)
        cin >> _A[i];

    int ans = sequence(_N, _A);
    cout << "ANSWER: " << ans << '\n';

    return 0;
}

#endif // Nhoksocqt1

Compilation message

sequence.cpp: In function 'int sub3()':
sequence.cpp:94:17: warning: unused variable 'cntPos' [-Wunused-variable]
   94 |             int cntPos = cnt[val[i]];
      |                 ^~~~~~
sequence.cpp: In function 'int sequence(int, std::vector<int>)':
sequence.cpp:110:83: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
  110 |         check3 &= (i <= 2 || val[i - 2] <= val[i - 1] || val[i - 2] >= val[i - 1] && val[i - 1] >= val[i]);
      |                                                          ~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
sequence.cpp:119:1: warning: control reaches end of non-void function [-Wreturn-type]
  119 | }
      | ^

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2392 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 0 ms 2396 KB Output is correct
4 Correct 1 ms 2396 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct
6 Correct 1 ms 2396 KB Output is correct
7 Correct 2 ms 2396 KB Output is correct
8 Correct 1 ms 2396 KB Output is correct
9 Correct 1 ms 2396 KB Output is correct
10 Correct 1 ms 2396 KB Output is correct
11 Correct 1 ms 2396 KB Output is correct
12 Correct 1 ms 2396 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2392 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 0 ms 2396 KB Output is correct
4 Correct 1 ms 2396 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct
6 Correct 1 ms 2396 KB Output is correct
7 Correct 2 ms 2396 KB Output is correct
8 Correct 1 ms 2396 KB Output is correct
9 Correct 1 ms 2396 KB Output is correct
10 Correct 1 ms 2396 KB Output is correct
11 Correct 1 ms 2396 KB Output is correct
12 Correct 1 ms 2396 KB Output is correct
13 Correct 220 ms 2572 KB Output is correct
14 Correct 197 ms 2392 KB Output is correct
15 Correct 21 ms 2392 KB Output is correct
16 Correct 23 ms 2396 KB Output is correct
17 Correct 9 ms 2396 KB Output is correct
18 Correct 188 ms 2604 KB Output is correct
19 Correct 169 ms 2396 KB Output is correct
20 Correct 144 ms 2396 KB Output is correct
21 Correct 174 ms 2396 KB Output is correct
22 Correct 184 ms 2560 KB Output is correct

Subtask #3
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2392 KB Output is correct
2 Correct 39 ms 9808 KB Output is correct
3 Correct 41 ms 11344 KB Output is correct
4 Correct 33 ms 9048 KB Output is correct
5 Correct 41 ms 11472 KB Output is correct
6 Correct 51 ms 11472 KB Output is correct
7 Correct 37 ms 9296 KB Output is correct
8 Correct 33 ms 9296 KB Output is correct
9 Correct 32 ms 8924 KB Output is correct

Subtask #4
0.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Incorrect 35 ms 8780 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #5
0.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 38 ms 9804 KB Output is correct
2 Correct 38 ms 11344 KB Output is correct
3 Incorrect 38 ms 11348 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #6
0.0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2392 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 0 ms 2396 KB Output is correct
4 Correct 1 ms 2396 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct
6 Correct 1 ms 2396 KB Output is correct
7 Correct 2 ms 2396 KB Output is correct
8 Correct 1 ms 2396 KB Output is correct
9 Correct 1 ms 2396 KB Output is correct
10 Correct 1 ms 2396 KB Output is correct
11 Correct 1 ms 2396 KB Output is correct
12 Correct 1 ms 2396 KB Output is correct
13 Correct 220 ms 2572 KB Output is correct
14 Correct 197 ms 2392 KB Output is correct
15 Correct 21 ms 2392 KB Output is correct
16 Correct 23 ms 2396 KB Output is correct
17 Correct 9 ms 2396 KB Output is correct
18 Correct 188 ms 2604 KB Output is correct
19 Correct 169 ms 2396 KB Output is correct
20 Correct 144 ms 2396 KB Output is correct
21 Correct 174 ms 2396 KB Output is correct
22 Correct 184 ms 2560 KB Output is correct
23 Incorrect 7 ms 3676 KB Output isn't correct
24 Halted 0 ms 0 KB -

Subtask #7
0.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2392 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 0 ms 2396 KB Output is correct
4 Correct 1 ms 2396 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct
6 Correct 1 ms 2396 KB Output is correct
7 Correct 2 ms 2396 KB Output is correct
8 Correct 1 ms 2396 KB Output is correct
9 Correct 1 ms 2396 KB Output is correct
10 Correct 1 ms 2396 KB Output is correct
11 Correct 1 ms 2396 KB Output is correct
12 Correct 1 ms 2396 KB Output is correct
13 Correct 220 ms 2572 KB Output is correct
14 Correct 197 ms 2392 KB Output is correct
15 Correct 21 ms 2392 KB Output is correct
16 Correct 23 ms 2396 KB Output is correct
17 Correct 9 ms 2396 KB Output is correct
18 Correct 188 ms 2604 KB Output is correct
19 Correct 169 ms 2396 KB Output is correct
20 Correct 144 ms 2396 KB Output is correct
21 Correct 174 ms 2396 KB Output is correct
22 Correct 184 ms 2560 KB Output is correct
23 Correct 39 ms 9808 KB Output is correct
24 Correct 41 ms 11344 KB Output is correct
25 Correct 33 ms 9048 KB Output is correct
26 Correct 41 ms 11472 KB Output is correct
27 Correct 51 ms 11472 KB Output is correct
28 Correct 37 ms 9296 KB Output is correct
29 Correct 33 ms 9296 KB Output is correct
30 Correct 32 ms 8924 KB Output is correct
31 Incorrect 35 ms 8780 KB Output isn't correct
32 Halted 0 ms 0 KB -