I have implemented a Heap-Based Priority Queue in Java but my challenge now is implementing an efficient Iterator that has a definite (increasing or decreasing) order of traversal. Is there any algorithm that does this at constant auxiliary space and time complexity of O(n)? The O(nlogn) is quite trivial. Als…
Tag: algorithm
How can I get all subarrays of a given array faster than O(N^2)?
I’m trying to print all subarrays of given array like below. I can print it with nested loops. But I want to know how to implement it with O(N) or O(2^N). Answer There are O(n^2) subarrays of an array in the first place. Printing them — no matter how you generate them — will always take at l…
How to output direction of shortest path?
This is a simple maze solver program. this is the simple maze i’m working on. I implemented a solution to output cordinates of the path as follow.(cordinates aquired from a BFS algorithm) but I want to output like below(omit same direction and only output direction and last coordinate to same direction)…
Code that takes a string and recognizes the number of consecutive letters
To do my job, I need a code that takes a word from the user, then recognizes the number of consecutive letters and outputs it in such a way that it prints the letter and the number of times it is repeated. Example 1 input: Example 1 output: Example 2 input: Example 2 output: Answer Here is one way. You
Get time period ( hour / half-hour / quarter hour ) of day
Is there any way to download every hour and another period of the day? I mean exactly the result in the form of a list. and and 14.03 means March 14 for the sake of the example. Of course it is possible to add this manually, but it would not be a particularly elegant solution. Is it possible to do
Checking a tree to be a BST
Here is my attempt to check whether a tree is a BST or not: Code works fine as tested with multiple test cases. But I am not sure if this is a good, clean approach. Recursive method is big it seems. I am dealing with scenarios like null left node, null right node, node itself null, both child nodes null
method to find the the distance of two characters of a string apart and entering them into an array
trying to solve this question for school “Given a string s and a character c, return a new list of integers of the same length as s where for each index i its value is set the closest distance of s[i] to c. You can assume c exists in s.” for example Input s = “aabaab” c = “b̶…
Index 16 out of bounds for length 16
I am trying to sort an array of x elements using quickSort but I am getting an error “Index 16 out of bounds for length 16” please help. Answer For an array of 16 elements the indexes are 0 to 15. Thus index 16 is not part of the array and you get the OutOfBoundsException.
Kth smallest number algorithm doing extra work?
So I’m preparing for a technical interview, and one of my practice questions is the Kth smallest number. I know that I can do a sort for O(n * log(n)) time and use a heap for O(n * log(k)). However I also know I can partition it (similar to quicksort) for an average case of O(n). The actual calculated a…
How to solve this java problem efficiently [closed]
Closed. This question needs details or clarity. It is not currently accepting answers. Want to improve this question? Add details and clarify the problem by editing this post. Closed 3 months ago. Improve this question I am trying to solve this problem and I worked out a solution but its too slow, this is my …