| | | 1 | | // -------------------------------------------------------------------------------- |
| | | 2 | | // Copyright (C) 2026 Eugene Eremeev (also known as Yevhenii Yeriemeieiv). |
| | | 3 | | // All Rights Reserved. |
| | | 4 | | // -------------------------------------------------------------------------------- |
| | | 5 | | // This software is the confidential and proprietary information of Eugene Eremeev |
| | | 6 | | // (also known as Yevhenii Yeriemeieiv) ("Confidential Information"). You shall not |
| | | 7 | | // disclose such Confidential Information and shall use it only in accordance with |
| | | 8 | | // the terms of the license agreement you entered into with Eugene Eremeev (also |
| | | 9 | | // known as Yevhenii Yeriemeieiv). |
| | | 10 | | // -------------------------------------------------------------------------------- |
| | | 11 | | |
| | | 12 | | namespace LeetCode.Algorithms.CountCoveredBuildings; |
| | | 13 | | |
| | | 14 | | /// <inheritdoc /> |
| | | 15 | | public sealed class CountCoveredBuildingsSimulation : ICountCoveredBuildings |
| | | 16 | | { |
| | | 17 | | /// <summary> |
| | | 18 | | /// Time complexity - O(m + n) |
| | | 19 | | /// Space complexity - O(n) |
| | | 20 | | /// </summary> |
| | | 21 | | /// <param name="n"></param> |
| | | 22 | | /// <param name="buildings"></param> |
| | | 23 | | /// <returns></returns> |
| | | 24 | | public int CountCoveredBuildings(int n, int[][] buildings) |
| | 3 | 25 | | { |
| | 3 | 26 | | Span<int> maxRow = stackalloc int[n + 1]; |
| | 3 | 27 | | Span<int> minRow = stackalloc int[n + 1]; |
| | 3 | 28 | | Span<int> maxCol = stackalloc int[n + 1]; |
| | 3 | 29 | | Span<int> minCol = stackalloc int[n + 1]; |
| | | 30 | | |
| | 3 | 31 | | minRow.Fill(n + 1); |
| | 3 | 32 | | minCol.Fill(n + 1); |
| | | 33 | | |
| | 34 | 34 | | for (var i = 0; i < buildings.Length; i++) |
| | 14 | 35 | | { |
| | 14 | 36 | | var building = buildings[i]; |
| | | 37 | | |
| | 14 | 38 | | var x = building[0]; |
| | 14 | 39 | | var y = building[1]; |
| | | 40 | | |
| | 14 | 41 | | maxRow[y] = Math.Max(maxRow[y], x); |
| | 14 | 42 | | minRow[y] = Math.Min(minRow[y], x); |
| | 14 | 43 | | maxCol[x] = Math.Max(maxCol[x], y); |
| | 14 | 44 | | minCol[x] = Math.Min(minCol[x], y); |
| | 14 | 45 | | } |
| | | 46 | | |
| | 3 | 47 | | var count = 0; |
| | | 48 | | |
| | 34 | 49 | | for (var i = 0; i < buildings.Length; i++) |
| | 14 | 50 | | { |
| | 14 | 51 | | var building = buildings[i]; |
| | | 52 | | |
| | 14 | 53 | | var x = building[0]; |
| | 14 | 54 | | var y = building[1]; |
| | | 55 | | |
| | 14 | 56 | | if (x > minRow[y] && x < maxRow[y] && y > minCol[x] && y < maxCol[x]) |
| | 2 | 57 | | { |
| | 2 | 58 | | count++; |
| | 2 | 59 | | } |
| | 14 | 60 | | } |
| | | 61 | | |
| | 3 | 62 | | return count; |
| | 3 | 63 | | } |
| | | 64 | | } |