Maximum alternating sum sequence.
In-depth solution and explanation for LeetCode 2036.
Maximum alternating sum sequence. In-depth solution and explanation for LeetCode 2036. Naive Approach: The simplest approach to solve this problem is to generate all possible non-empty subsequences of the array and calculate the sum of each subsequence of the array. Jul 30, 2021 · The alternating sum of a 0-indexed array is defined as the sum of the elements at even indices minus the sum of the elements at odd indices. Maximum Alternating Subsequence Sum in Python, Java, C++ and more. Given a 0-indexed integer array nums, return _themaximum alternating subarray sum of any subarray of _nums. Follow the steps below to solve the problem efficiently: Jul 10, 2020 · Learn how to find the maximum sum of an alternating subsequence in C++ with our comprehensive guide and examples. (1pt) Now initialize your sitbproblems. In this video, we will learn how to find the maximum error when approximating an alternating series by a finite term of the series. me May 15, 2019 · The alternating series estimation theorem gives us a way to approximate the sum of an alternating series with a remainder or error that we can calculate. We define Ou] as the value of the maximum odd-length alternating sum subsequence of the first i elements of S, and Eli) as the value of the maximum even-length alternating sum subsequence of the first i elements of S a. Find the solution of Maximum Alternating Subsequence Sum Leetcode question with step by step explanation in 3 approaches and 3 solutions in languages like Java, CPP, Python. You are given a sequence of n num- bers x1, , xn. Can you solve this real interview question? Maximum Alternating Subsequence Sum - The alternating sum of a 0-indexed array is defined as the sum of the elements at even indices minus the sum of the elements at odd indices. This works because the best possible sequence should always end in the addition phase to maximize the value. . Given an array of integers, we need to choose elements alternately such that the sum of Sep 16, 2022 · Find the maximum sum of maximum size alternate subsequence of a given sequence that is, in a subsequence sign of each adjacent element is opposite for example if the first one is positive then the second one has to be negative followed by another positive integer and so on. Alternating sums also arise in other cases. Jan 1, 2025 · Problem A subarray of a 0-indexed integer array is a contiguous non-empty sequence of elements within an array. After … A subarray of a 0-indexed integer array is a contiguous non-empty sequence of elements within an array. Jul 23, 2025 · Given an array, the task is to find sum of maximum sum alternating subsequence starting with first element. In every iteration of both the loops, update sum as max (sum, sumSoFar). The alternating sum of a 0-indexed array is defined as the sum of the elements at even indices minus the sum of the elements at odd indices. Feb 22, 2021 · Maximum Alternating Subsequence Sum. Maximum Product of Subsequences With an Alternating Sum Equal to K - You are given an integer array nums and two integers, k and limit. There is a solution like, first sort the array in to some auxiliary memory, then apply Longest Common Sub-Sequence method to the original array and the sorted array, with sum (not the length) of common sub-sequence in the 2 arrays as the entry into the table (Memoization). Question: Maximum alternating subsequence sum. length) is nums[i] - nums[i+1] + nums[i+2] - +/- nums[j]. Your task is to find a non-empty subsequence of nums that: * Has an alternating sum equal to k. In this section we introduce alternating series—those series whose terms alternate in sign. (ipt) How can your subproblems solve the given problem? b. For example, the alternating harmonic series is . We will show in a later chapter that these series often arise when studying power series. This video is part of the series to impart industry-level web development and programming skills in the community. The alternating subarray sum of a subarray that ranges from index i to j (inclusive, 0 <= i <= j < nums. Jul 23, 2025 · Initialize a variable, say sum as 0, which will hold a maximum alternating subarray sum and a variable, say sumSoFar, to store the sum of subarrays starting from even indices in the 1 st loop and the sum starting from odd indices, in the 2 nd loop. Hi Everyone, this is the 9th video of our new Playlist "DP Concepts & Qns". Maximum Alternating Subsequence Sum - Dynamic Programming - Leetcode 1911 - Python NeetCode 1M subscribers Subscribe Jul 15, 2020 · Therefore, the subsequence with the maximum sum is {2, -1, 2, -3}, formed by selecting the maximum element from each of the sequences. Example 1: Input An alternating subsequence is a sequence of elements where the elements alternate between being greater than and less than their adjacent elements. This can also solve the problem Total running time is O (nlogn)+O (n^2) => O (n^2) Space is O (n) + O (n^2) => O (n^2 Oct 20, 2021 · Welcome to Subscribe On Youtube2036 - Maximum Alternating Subarray Sum Posted on October 20, 2021 · 1 minute read Dec 21, 2022 · Let A is given an array of length N We define a 2D array las [n] [2] such that las [i] [0] contains the longest alternating subsequence ending at index i and the last element is greater than its previous element las [i] [1] contains the longest alternating subsequence ending at index i and the last element is smaller than its previous element, then we have the following recurrence relation Alternating sum An alternating sum is a series of real numbers in which the terms alternate sign. Jul 23, 2023 · The Maximum Alternating Sum problem involves finding the maximum alternating sum of elements in an array. Maximum Alternating Subsequence Sum My contact details Instagram :- / frazmohammad Connect with me on LinkedIn :- / mohammad-f-bb4886157 Telegram Group https://t. For instance, the divisibility rule for 11 is to take the alternating sum of the digits of the integer in question and check if the result is divisble by 11. * Maximizes the product of all its numbers without the product exceeding limit. For example, the alternating sum of [4,2,5,3] is (4 + 5) - (2 + 3) = 4. Examples Leetcode solution 5782. Your goal is to find the maximum alternating sum of a contiguous subsequence within this sequence. To use the theorem, the alternating series must follow two rules. * For example, the alternating sum of [4,2,5,3] is (4 + 5) - (2 + 3) = 4. Better than official and forum solutions. Therefore, the required output is 13. At the end of the traversal, even_sum holds the maximum alternating sum over all subsequences. Intuitions, example walk through, and complexity analysis. We also provide professional courses with live classes and placement opportunities. Today we will solve another 1-D DP problem Maximum Alternating Subsequence Sum (Leetcode-1911) using Recursion Jul 23, 2025 · Sum of the subsequence { arr [1], arr [3] } is equal to 13, which is the maximum possible sum of any subsequence of the array. Maximum Alternating Subsequence Sum - The alternating sum of a 0-indexed array is defined as the sum of the elements at even indices minus the sum of the elements at odd indices. However, it's important to note that this alternation should start with either a decreasing sequence followed by an increasing sequence or vice versa. Maximum Alternating Subarray Sum in Python, Java, C++ and more. Here alternating sequence means first decreasing, then increasing, then decreasing, In-depth solution and explanation for LeetCode 1911. The alternating subarray sum of a subarray that ranges from index i to j (inclusive , 0 <= i <= j < nums. Nov 16, 2022 · In this section we will discuss how the Integral Test, Comparison Test, Alternating Series Test and the Ratio Test can, on occasion, be used to estimating the value of an infinite series. Given a 0-indexed integer array nums, return the maximum alternating subarray sum of any subarray of nums. c. A subsequence of an array is a new array generated from the original array by deleting some elements (possibly none) without changing the remaining elements' relative order. Use the alternating series estimation theorem in conjunction with your knowledge of power series to control errors in estimation. Given an array nums, return the maximum alternating sum of any subsequence of nums (after reindexing the elements of the subsequence). 4fuhuko0yckwycwku9pz3d3u8lxoqzoi9medgjvvq