All Hard Articles

Operating Systems | Process Synchronization | Question 5

The atomic fetch-and-set x, y instruction unconditionally sets the memory location x to 1 and fetches the old value of x in y without allowing… Read More

Operating Systems-Process Management

Process Management

Operating Systems Questions

Operating Systems | Process Management | Question 6

Consider the following code fragment: if (fork() == 0) { a = a + 5; printf("%d,%d\n", a, &a); } else { a = a –5;… Read More

Operating Systems-Process Management

Process Management

Operating Systems

Data Structures | Linked List | Question 4

Which of the following sorting algorithms can be used to sort a random linked list with minimum time complexity? (A) Insertion Sort (B) Quick Sort… Read More

Data Structures

Data Structures-Linked List

Linked Lists

Data Structures

DSA

Ternary Search Tree

A ternary search tree is a special trie data structure where the child nodes of a standard trie are ordered as a binary search tree. … Read More

Advanced Data Structure

DSA

Measure one litre using two vessels and infinite water supply

There are two vessels of capacities 'a' and 'b' respectively. We have infinite water supply. Give an efficient algorithm to make exactly 1 litre of water in one of the vessels.

Modular Arithmetic

DSA

Mathematical

Nvidia Interview | Set 1

Following is my interview experience for NVIDIA internship. I faced three telephonic rounds in my room. Round 1: Round 1 was a combination of HR… Read More

Nvidia

Experiences

Interview Experiences

Amazon Interview | Set 14

Team : Transportation Location :Hyderabad Round 1 (Online Test) Q1. Find the kth largest value in a BST Q2. Swap the alternate nodes in a singly linked… Read More

Amazon

DSA

Experiences

Interview Experiences

Mathematical

Tree

Directi Interview | Set 1

Written Round: 1) Given a binary tree, such that each node contains a number. Find the maximum possible sum in going from one leaf node… Read More

Directi

number-theory

Arrays

DSA

Experiences

Interview Experiences

Tree

Optimal Binary Search Tree | DP-24

An Optimal Binary Search Tree (OBST), also known as a Weighted Binary Search Tree, is a binary search tree that minimizes the expected search cost.… Read More

Binary Search Tree

DSA

Dynamic Programming

Program to find amount of water in a given glass

There are some glasses with equal capacity as 1 litre. The glasses are kept as follows: 1 2 3 4 5 6 7 8 9… Read More

Amazon

D-E-Shaw

DSA

Dynamic Programming

Mathematical

Recursion

Amazon Interview | Set 12

I am very thankful to geeksforgeeks team for such a great site. I got offer from Amazon. Written Test It was online test on interviewstreet.… Read More

Amazon

Experiences

Interview Experiences

Closest Pair of Points using Divide and Conquer algorithm

We are given an array of n points in the plane, and the problem is to find out the closest pair of points in the… Read More

Closest Pair of Points

Divide and Conquer

DSA

Geometric

C# Program for Dijkstra’s shortest path algorithm | Greedy Algo-7

Given a graph and a source vertex in the graph, find shortest paths from source to all vertices in the given graph. Dijkstra’s algorithm is… Read More

Dijkstra

C# Programs

Construction of Longest Increasing Subsequence (N log N)

In my previous post, I have explained about longest increasing sub-sequence (LIS) problem in detail. However, the post only covered code related to querying size of… Read More

LIS

Arrays

DSA

Prim’s MST for Adjacency List Representation | Greedy Algo-6

We recommend reading the following two posts as a prerequisite to this post. Greedy Algorithms | Set 5 (Prim’s Minimum Spanning Tree (MST)) Graph and its… Read More

MST

DSA

Graph

Greedy

Amazon Interview | Set 10

Recently I got interviewed at Amazon Hyderabad. I just wanted to share my experience. Hope someone gets little help from this. 1. Telephonic a. In… Read More

Amazon

Experiences

Interview Experiences

Select a random number from stream, with O(1) space

Given a stream of numbers, generate a random number from the stream. You are allowed to use only O(1) space and the input is in… Read More

array-stream

Random Algorithms

DSA

Mathematical

Randomized

Huffman Coding | Greedy Algo-3

Huffman coding is a lossless data compression algorithm. The idea is to assign variable-length codes to input characters, lengths of the assigned codes are based… Read More

Amazon

encoding-decoding

Huffman Coding

Morgan Stanley

priority-queue

Samsung

United Health Group

DSA

Greedy

Heap

Branch prediction macros in GCC

One of the most used optimization techniques in the Linux kernel is ” __builtin_expect”. When working with conditional code (if-else statements), we often know which… Read More

AdvanceC

C-Macro & Preprocessor

c-puzzle

GCC

C Language

Given a sequence of words, print all anagrams together | Set 2

Given an array of words, print all anagrams together. For example, if the given array is {“cat”, “dog”, “tac”, “god”, “act”}, then output may be… Read More

Amazon

anagram

Snapdeal

Advanced Data Structure

DSA

Hash

Strings