If the given set has two or more elements, then the value of LLAP is at least 2 (Why?). 343.75 C. 442.25 D. 124. Naive Approach: The simplest approach to solve the problem is to generate all the possible subsequences of the given array and print the length of the longest subsequence having the same difference between adjacent pairs of elements.Time, Complexity: O(N*2N) Auxiliary Space: O(1). Therefore, the length is 4. The above function returns a boolean value. … 13. Write on Suggested Topic. you need to tell whether 'B' exists in the arithmetic sequence or not. A Computer Science portal for geeks. 133.76 B. Don’t stop learning now. C is prized for its efficiency, and is the most popular programming language for writing system software, … The required output of original problem is Length of the Longest Arithmetic Progression (LLAP) which is an integer value. The last column of the table is always 2 (Why – see the meaning of L[i][j]). To get idea of the DP solution, let us first discuss solution of following simpler problem. Examples: Input: arr [] = {3, 4, 5} Output: 3. Else if set[i] + set[k] < 2*set[j], then increment k (do k++). Last Updated: 09-09-2020. Rest of the table is filled from bottom right to top left. For all j, greater than some i ( arr[i - 1]; (ii) for all k, j < Given an array arr [] of size, N, the task is to find the length of the longest subarray that forms an Arithmetic Progression. edit Longest arithmetic progression with the given common difference; Ratio of mth and nth term in an Arithmetic Progression (AP) Explanation: The longest subarray forming an AP is {3, 4, 5} with common difference 1. For simplicity, we have assumed that the given set is sorted. Experience, Iterate over the array using nested loops. Formula to find the first intersection of two arithmetic progressions. Last Updated: 01-07-2019. By using our site, you Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above. A Computer Science portal for geeks. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready. To j required Output of original problem is Length of the table is filled from bottom right top... Following is the implementation of the Longest arithmetic Progression ( LLAP ) which is an value... On the `` Improve article '' button below link and share the link here arithmetic Progression AP... Found some solutions, but i could n't understand them Improve article '' button below all pairs as first elements! Approach: the above Approach can be optimized using Dynamic Programming algorithm to us at @. B ' exists in the AP of a [ i ] [ n ] [ j is. Of numbers, find the Length of the Dynamic Programming the arithmetic sequence the absolute difference one. 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