oj.uz

Submission #751613

# Submission time Handle Problem Language Result Execution time Memory
751613 2023-06-01T01:19:44 Z rxlfd314 Sequence (APIO23_sequence) C++17
11 / 100
 344 ms 31600 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 = 1;
		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 1 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 1 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 344 ms 468 KB Output is correct
14 Correct 341 ms 392 KB Output is correct
15 Correct 336 ms 388 KB Output is correct
16 Correct 342 ms 460 KB Output is correct
17 Correct 316 ms 392 KB Output is correct
18 Correct 264 ms 340 KB Output is correct
19 Correct 344 ms 392 KB Output is correct
20 Correct 341 ms 392 KB Output is correct
21 Incorrect 342 ms 388 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 82 ms 25812 KB Output is correct
3 Correct 79 ms 25836 KB Output is correct
4 Correct 48 ms 18012 KB Output is correct
5 Correct 81 ms 24892 KB Output is correct
6 Correct 78 ms 24904 KB Output is correct
7 Incorrect 50 ms 18388 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 19076 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 119 ms 31600 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 1 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 344 ms 468 KB Output is correct
14 Correct 341 ms 392 KB Output is correct
15 Correct 336 ms 388 KB Output is correct
16 Correct 342 ms 460 KB Output is correct
17 Correct 316 ms 392 KB Output is correct
18 Correct 264 ms 340 KB Output is correct
19 Correct 344 ms 392 KB Output is correct
20 Correct 341 ms 392 KB Output is correct
21 Incorrect 342 ms 388 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 1 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 344 ms 468 KB Output is correct
14 Correct 341 ms 392 KB Output is correct
15 Correct 336 ms 388 KB Output is correct
16 Correct 342 ms 460 KB Output is correct
17 Correct 316 ms 392 KB Output is correct
18 Correct 264 ms 340 KB Output is correct
19 Correct 344 ms 392 KB Output is correct
20 Correct 341 ms 392 KB Output is correct
21 Incorrect 342 ms 388 KB Output isn't correct
22 Halted 0 ms 0 KB -