Before jumping directly into the patterns, please revise the following data structures. Arrays ArrayList LinkedList Stack Queue HashMap HashSet Trie Important patterns to remember for DSA interviews Two Pointers Sliding Window Modified B...
To see the question, click here. Naive Approach The idea is to use a recursive approach to compute the Fibonacci sequence. If n is 0 or 1, return n directly, as these are the base cases for the Fibonacci sequence. For any other value of n, recursivel...
To see the question, click here. Naive Approach The idea is to iterate through each element in nums1 and then search for this element in nums2. Once found, look for the next greater element in nums2 by scanning the elements following the found elemen...
To see the question, click here. Naive Approach The idea is to store all the values of the list nodes in an array, sort them using the Arrays.sort method, and then construct the linked list to return it as the answer. // TC: O(nlogn) // SC: O(n) imp...
To see the question, click here. Naive Approach The idea is to store the elements in a list. At each stage of adding an element, we will sort the list because the elements may not be added to the list in a sorted fashion. // TC: O(nlogn) for addNum a...
To see the question, click here. Naive Approach To find the kth largest element, we can first sort the array and then return the nums.length - k th element. // TC: O(nlogn) // SC: O(1) import java.util.Arrays; class KthLargestElement { public ...
In Java, heaps are typically implemented using the PriorityQueue class, which is part of the java.util package. A heap is a specialized tree-based data structure that satisfies the heap property. The PriorityQueue class provides an implementation of ...
To see the question, click here. Naive Approach The idea is to use the concept of backtracking. Initialize a result list to store all valid combinations and a temporary list temp to store the current combination being explored. Assume a recursive fun...
To see the question, click here. Naive Approach The idea is to generate all possible subsets of a given array nums using a backtracking approach. Initialize a result list to store all subsets and a temporary list temp to store the current subset bein...