Instead of storing the entire Padovan sequence in a list, you can optimize the space complexity by just storing the last three elements of the sequence. This way, you can calculate the next element based on these three elements without storing the entire sequence.
Question
Instead of storing the entire Padovan sequence in a list, you can optimize the space complexity by just storing the last three elements of the sequence. This way, you can calculate the next element based on these three elements without storing the entire sequence.
Solution
Sure, here's how you can do it:
-
Initialize three variables, say
p0,p1, andp2to represent the last three elements of the Padovan sequence. You can start withp0 = p1 = 1andp2 = 0as the first three elements of the sequence. -
To calculate the next element of the sequence, use the formula
p_next = p0 + p2. This is based on the recurrence relation of the Padovan sequence. -
After calculating the next element, you need to update the last three elements. Set
p0 = p1,p1 = p2, andp2 = p_next. -
Repeat steps 2 and 3 for as many elements as you want to generate in the sequence.
This way, you only need to store the last three elements at any point, reducing the space complexity from O(n) to O(1).
Similar Questions
Write a Python program using functions and recursion to generate and display the first 15 numbers of the Padovan sequence. The Padovan sequence begins with the first three terms as 1, 1, and 1, and each subsequent term is the sum of the previous two terms. For example, the first few terms of the Padovan sequence are: 1, 1, 1, 2, 2, 3, 4, 5, 7, 9, 12, 16, 21, 28, 37,.Note: The Padovan sequence is a sequence of numbers similar to the Fibonacci sequence, where each term is the sum of the previous two terms.
Given a number n, find the nthย number in the Padovan Sequence.A Padovan Sequence is a sequence which is represented by the following recurrence relationP(n) = P(n-2) + P(n-3)P(0) = P(1) = P(2) = 1Note: Since the output may be too large, compute the answer modulo 10^9+7.
Given an array, find the length of the longest subsequence whose elements can be re-arranged in a strictly increasing contiguous order. The difference between 2 adjacent elements in the subsequence, after re-arrangement, should be exactly 1.Input FormatThe first line of input contains T - the number of test cases. It's followed by 2T lines. The first line of each test case contains N - size of the array. The next line contains N integers - the elements of the array.Output FormatFor each test case, print the length of the longest subsequence, separated by a new line.Constraints1 <= T <= 10001 <= N <= 10000-100000 <= ar[i] <= 100000ExampleInput3821 -22 -22 5 -31 -24 5 -231018 -33 31 33 30 -14 32 30 16 1766 3 8 5 2 5Output342ExplanationTest Case 1Subsequence is: -22, -24, -23.Test Case 2Subsequence is: 31, 33, 30, 32.Test Case 3Subsequence is: 6, 5 or 3, 2.
longest consecutive elementsYou need to write a function that takes an unsorted array of integers as input and returns the length of the longest consecutive elements sequence in the array. A consecutive elements sequence is a subarray where the elements are adjacent in value, such as [1, 2, 3, 4] or [5, 6, 7, 8]. The order of the elements in the input array does not matter.For example, given the input array [100, 4, 200, 1, 3, 2], the longest consecutive elements sequence is [1, 2, 3, 4], which has a length of 4. Therefore, your function should return 4.In this case, there are no consecutive elements in the array, so the length of the longest consecutive element sequence is 1.Testcase:Input11 ย // no of elements of array8 10 12 14 1 2 3 4 5 6 7 ย // array elementsOutput:8
You are given a sequence [a1,โฆ,an][๐1,โฆ,๐๐] where each element ai๐๐ is either 00 or 11. You can apply several (possibly zero) operations to the sequence. In each operation, you select two integers 1โคlโคrโค|a|1โค๐โค๐โค|๐| (where |a||๐| is the current length of a๐) and replace [al,โฆ,ar][๐๐,โฆ,๐๐] with a single element x๐ฅ, where x๐ฅ is the majority of [al,โฆ,ar][๐๐,โฆ,๐๐].Here, the majority of a sequence consisting of 00 and 11 is defined as follows: suppose there are c0๐0 zeros and c1๐1 ones in the sequence, respectively.If c0โฅc1๐0โฅ๐1, the majority is 00.If c0<c1๐0<๐1, the majority is 11.For example, suppose a=[1,0,0,0,1,1]๐=[1,0,0,0,1,1]. If we select l=1,r=2๐=1,๐=2, the resulting sequence will be [0,0,0,1,1][0,0,0,1,1]. If we select l=4,r=6๐=4,๐=6, the resulting sequence will be [1,0,0,1][1,0,0,1].Determine if you can make a=[1]๐=[1] with a finite number of operations.InputEach test contains multiple test cases. The first line contains the number of test cases t๐ก (1โคtโค4โ 1041โค๐กโค4โ 104). Description of the test cases follows.The first line of each testcase contains one integer n๐ (1โคnโค2โ 1051โค๐โค2โ 105).The second line of each testcase contains a string consisting of 00 and 11, describing the sequence a๐.It's guaranteed that the sum of n๐ over all testcases does not exceed 2โ 1052โ 105.OutputFor each testcase, if it's possible to make a=[1]๐=[1], print YES. Otherwise, print NO. You can output the answer in any case (upper or lower). For example, the strings yEs, yes, Yes, and YES will be recognized as positive responses.ExampleinputCopy5101120191000000019000011000outputCopyNoYesNoYesNoNoteIn the fourth testcase of the example, initially a=[1,0,0,0,0,0,0,0,1]๐=[1,0,0,0,0,0,0,0,1]. A valid sequence of operations is:Select l=2,r=8๐=2,๐=8 and apply the operation. a๐ becomes [1,0,1][1,0,1].Select l=1,r=3๐=1,๐=3 and apply the operation. a๐ becomes [1][1].
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.