oj.uz

Submission #751612

# Submission time Handle Problem Language Result Execution time Memory
751612 2023-06-01T01:18:46 Z rxlfd314 Sequence (APIO23_sequence) C++17
11 / 100
 353 ms 31628 KB 
#include "sequence.h"
#include <bits/stdc++.h>
using namespace std;
using ari2 = array<int, 2>;

int sequence(int N, vector<int> A) {
	if (N <= 2000) {
		int ans = 0;
		for (int i = 0; i < N; i++) {
			vector<int> cnt(N+1, 0);
			multiset<ari2> stuff;
			cnt[A[i]]++;
			stuff.insert({A[i], -i});
			auto it = stuff.begin();
			for (int j = i+1; j < N; j++) {
				stuff.insert({A[j], -j});
				cnt[A[j]]++;
				if (ari2{A[j], -j} < *it && (j - i & 1)) {
					it--;
				} else if (ari2{A[j], -j} > *it && !(j - i & 1)) {
					it++;
				}
				ans = max(ans, cnt[(*it)[0]]);
			}
		}
		return ans;
	}
	
	int middle = max_element(A.begin(), A.end()) - A.begin();
	bool mountain = true;	
	for (int i = middle - 1; i >= 0 && mountain; i--) {
		mountain &= A[i] <= A[i+1];
	}
	for (int i = middle + 1; i < N && mountain; i++) {
		mountain &= A[i] <= A[i-1];
	}
	if (mountain) {
		vector<int> inds[N];
		for (int i = 0; i < N; i++) {
			inds[A[i]-1].push_back(i);
		}
		
		int ans = 0;
		for (int ii = 0; ii < N; ii++) {
			if (inds[ii].size() < 2) {
				ans = max(ans, (int)inds[ii].size());
				continue;
			}
			int l1 = inds[ii][0], r1 = -1, l2 = -1, r2 = inds[ii].back();
			for (int i = 1; i < inds[ii].size(); i++) {
				if (inds[ii][i-1]+1 < inds[ii][i]) {
					r1 = inds[ii][i-1];
					l2 = inds[ii][i];
					break;
				}
			}
			if (r1 < 0) {
				ans = max(ans, r2 - l1 + 1);
			} else {
				int gap = l2 - r1 - 1;
				if (gap > r1 - l1 + 1 + r2 - l2 + 1) {
					if (l1 + N - r2 - 1 >= gap - (r1 - l1 + 1 + r2 - l2 + 1)) {
						ans = max(ans, r1 - l1 + 1 + r2 - l2 + 1);
					}
				} else {
					ans = max(ans, r1 - l1 + 1 + r2 - l2 + 1);
				}
			}
		}
		
		return ans;
	}
}

Compilation message

sequence.cpp: In function 'int sequence(int, std::vector<int>)':
sequence.cpp:18:36: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
   18 |     if (ari2{A[j], -j} < *it && (j - i & 1)) {
      |                                  ~~^~~
sequence.cpp:20:44: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
   20 |     } else if (ari2{A[j], -j} > *it && !(j - i & 1)) {
      |                                          ~~^~~
sequence.cpp:50:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |    for (int i = 1; i < inds[ii].size(); i++) {
      |                    ~~^~~~~~~~~~~~~~~~~
sequence.cpp:73:1: warning: control reaches end of non-void function [-Wreturn-type]
   73 | }
      | ^

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 2 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct

Subtask #2
0.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 2 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 343 ms 460 KB Output is correct
14 Correct 345 ms 340 KB Output is correct
15 Correct 347 ms 396 KB Output is correct
16 Correct 336 ms 392 KB Output is correct
17 Correct 348 ms 388 KB Output is correct
18 Correct 264 ms 404 KB Output is correct
19 Correct 353 ms 392 KB Output is correct
20 Correct 344 ms 392 KB Output is correct
21 Incorrect 351 ms 408 KB Output isn't correct
22 Halted 0 ms 0 KB -

Subtask #3
0.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 87 ms 25796 KB Output is correct
3 Correct 81 ms 25816 KB Output is correct
4 Correct 53 ms 18000 KB Output is correct
5 Correct 91 ms 24904 KB Output is correct
6 Correct 83 ms 24900 KB Output is correct
7 Incorrect 54 ms 18376 KB Output isn't correct
8 Halted 0 ms 0 KB -

Subtask #4
0.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Incorrect 47 ms 19072 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #5
0.0 / 13.0

# Verdict Execution time Memory Grader output
1 Incorrect 126 ms 31628 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #6
0.0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 2 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 343 ms 460 KB Output is correct
14 Correct 345 ms 340 KB Output is correct
15 Correct 347 ms 396 KB Output is correct
16 Correct 336 ms 392 KB Output is correct
17 Correct 348 ms 388 KB Output is correct
18 Correct 264 ms 404 KB Output is correct
19 Correct 353 ms 392 KB Output is correct
20 Correct 344 ms 392 KB Output is correct
21 Incorrect 351 ms 408 KB Output isn't correct
22 Halted 0 ms 0 KB -

Subtask #7
0.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 2 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 343 ms 460 KB Output is correct
14 Correct 345 ms 340 KB Output is correct
15 Correct 347 ms 396 KB Output is correct
16 Correct 336 ms 392 KB Output is correct
17 Correct 348 ms 388 KB Output is correct
18 Correct 264 ms 404 KB Output is correct
19 Correct 353 ms 392 KB Output is correct
20 Correct 344 ms 392 KB Output is correct
21 Incorrect 351 ms 408 KB Output isn't correct
22 Halted 0 ms 0 KB -