| | | 1 | | // -------------------------------------------------------------------------------- |
| | | 2 | | // Copyright (C) 2025 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.CountTheHiddenSequences; |
| | | 13 | | |
| | | 14 | | /// <inheritdoc /> |
| | | 15 | | public class CountTheHiddenSequencesPrefixSum : ICountTheHiddenSequences |
| | | 16 | | { |
| | | 17 | | /// <summary> |
| | | 18 | | /// Time complexity - O(n) |
| | | 19 | | /// Space complexity - O(1) |
| | | 20 | | /// </summary> |
| | | 21 | | /// <param name="differences"></param> |
| | | 22 | | /// <param name="lower"></param> |
| | | 23 | | /// <param name="upper"></param> |
| | | 24 | | /// <returns></returns> |
| | | 25 | | public int NumberOfArrays(int[] differences, int lower, int upper) |
| | 3 | 26 | | { |
| | 3 | 27 | | var minPrefix = 0; |
| | 3 | 28 | | var maxPrefix = 0; |
| | 3 | 29 | | var prefixSum = 0; |
| | 3 | 30 | | var bound = upper - lower; |
| | | 31 | | |
| | 26 | 32 | | foreach (var difference in differences) |
| | 9 | 33 | | { |
| | 9 | 34 | | prefixSum += difference; |
| | | 35 | | |
| | 9 | 36 | | minPrefix = Math.Min(minPrefix, prefixSum); |
| | 9 | 37 | | maxPrefix = Math.Max(maxPrefix, prefixSum); |
| | | 38 | | |
| | 9 | 39 | | if (maxPrefix - minPrefix > bound) |
| | 1 | 40 | | { |
| | 1 | 41 | | return 0; |
| | | 42 | | } |
| | 8 | 43 | | } |
| | | 44 | | |
| | 2 | 45 | | return bound - (maxPrefix - minPrefix) + 1; |
| | 3 | 46 | | } |
| | | 47 | | } |