An XOR-linked list is a memory-efficient version of a doubly linked list. Instead of each node storing separate next and prev pointers, each node contains a single field called both, which stores the result of the XOR operation on the memory addresses of the next and previous nodes.
January 4, 2025 | dsa, DSA Sheet, Google | No comments
Problem Statement (Asked By Jane Street) The function cons(a, b) creates a pair of two elements. Implement two functions: For instance: Below is the implementation of cons: Your task is to define the car and cdr functions. Disclaimer: Try solving the problem on your own first! Use this solution only as a reference to learn and […]
January 3, 2025 | dsa, DSA Sheet, Jane Street | No comments
Problem Statement (Asked By Stripe) You are given an array of integers. Your task is to find the smallest missing positive integer in O(N) time using O(1) additional space. In other words, identify the smallest positive number that is not present in the array. The array may include: You are allowed to modify the input […]
January 2, 2025 | dsa, DSA Sheet, Stripe | No comments
Given the root of a binary tree, create two functions:
serialize(root) – Converts the binary tree into a string representation.
deserialize(s) – Reconstructs the binary tree from its string representation.
January 1, 2025 | array, dsa, DSA Sheet, Google | No comments
Problem Statement (Asked By Uber) Given a list of integers, return a new list such that each element at index i of the new list is the product of all the elements in the original list except the one at i. For instance, if the input is [1, 2, 3, 4, 5], the expected output […]
December 30, 2024 | Algorithm, array, Data Structure, dsa, Uber | No comments
Problem Statement (Asked By Google) Given a list of integers and a target number k, determine if there exist two numbers in the list whose sum equals k. For example, given [10, 15, 3, 7] and k = 17, return True because 10 + 7 = 17. Bonus: Can you solve this in a single […]
December 29, 2024 | array, dsa | No comments
Problem Statement: Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses. Example 1: Input: n = 3 Output: [“((()))”,”(()())”,”(())()”,”()(())”,”()()()”]Example 2: Input: n = 1 Output: [“()”] Solution: This problem can be solved using the concept of backtracking, Let’s see how to approach it. We have to write a function generate([], left, right, […]
September 24, 2024 | 23 DSA Patterns | No comments
Given an integer A. Compute and return the square root of A. If A is not a perfect square, return floor(sqrt(A)). The value of A can cross the range of Integer.
August 10, 2023 | DSA Sheet | No comments
Given a zero-based permutation nums (0-indexed), build an array ans of the same length where ans[i] = nums[nums[i]] for each 0 <= i < nums.length and return it. A zero-based permutation nums is an array of distinct integers from 0 to nums.length - 1 (inclusive).
August 9, 2023 | DSA Sheet | No comments
A heap is a specialized tree-based data structure that satisfies the heap property. It is commonly used to implement priority queues and efficient sorting algorithms like heap sort.
June 10, 2023 | Algorithm, Data Structure | No comments