So you think you are clever, right? Then here is your chance to pit your brain against some of the world’s hardest logic puzzles ever created. 1. 10 identical bottles of pills We have 10 identical bottles of identical pills (each bottle contain hundred of pills). Out of 10 bottles 9 have 1 gram of … Read More →

## Count Total Set Bits in All Numbers From 1 to N

Problem: Given a positive integer n, count the total number of set bits in binary representation of all numbers from 1 to n. Examples: Input: n = 3 Output: 4 Input: n = 6 Output: 9 Input: n = 7 Output: 12 Input: n = 8 Output: 13 Solution: The solution is to run a … Read More →

## Snapdeal Interview Questions – Set 4

Software Development Engineer In Test Interview I applied through a recruiter. The process took 1 day. I interviewed at Snapdeal (Gurgaon, Haryana). 2 Round was on developing the automation framework approaches and general java based algorithm to some complex variations to puzzle you. Q1. Find the first non repetitive element in an array. Q2. Implement … Read More →

## Shopclues Interview Questions – Set 1

Hi my name is Surender. Shopclues recently visited our campus for recruitment.I’m mentioning below there interview process and the interview questions asked. Three Rounds(1 written + 2 interviews) Round 1 (Written Test) It consisted of eleven aptitude questions which were to be solved in one hour. For software profile there were five more questions based … Read More →

## 2 Player and N Coin – Strategy Puzzle

Puzzle: There are n coins in a line. (Assume n is even). Two players take turns to take a coin from one of the ends of the line until there are no more coins left. The player with the larger amount of money wins. Would you rather go first or second? Does it matter? Assume … Read More →

## Find the Maximum of Two Numbers Without Using if-else

Find the maximum and minimum of two integers without branching i.e. if condition. Solution: Minimum of two numbers can be found from the following: Min(x,y) = y ^ ((x ^ y) & -(x < y)) It works because if x < y, then -(x < y) will be all ones, so r = y ^ … Read More →

## Find the Element that Appears Once

Problem: Given an array where every element occurs three times, except one element which occurs only once. Find the element that occurs once. Expected time complexity is O(n) and O(1) extra space. Examples: Input: arr[] = {10, 1, 10, 3, 10, 1, 1, 2, 3, 3} Output: 2 Solution: If O(1) space constraint was not … Read More →

## Check if a Singly Linked List is Palindrome

Given a singly linked list, determine if its a palindrome. Return 1 or 0 denoting if its a palindrome or not, respectively. Notes: – Expected solution is linear in time and constant in space. For example, List 1–>2–>1 is a palindrome. List 1–>2–>3 is not a palindrome. Solution: This method takes O(n) time and O(1) … Read More →

## Minimum no Of Aircraft Puzzle

Puzzle: On Bagshot Island, there is an airport. The airport is the home base of an unlimited number of identical airplanes. Each airplane has a fuel capacity to allow it to fly exactly 1/2 way around the world, along a great circle. The planes have the ability to refuel in flight without loss of speed … Read More →

## Dynamic Memory Allocation (Stack vs Heap)

The Stack What is the stack? It’s a special region of your computer’s memory that stores temporary variables created by each function (including the main() function). The stack is a “LIFO” (last in, first out) data structure, that is managed and optimized by the CPU quite closely. Every time a function declares a new variable, … Read More →

## Chickens and Rabbits | Math Puzzle

Puzzle: There are several chickens and rabbits in a cage (with no other types of animals). There are 72 heads and 200 feet inside the cage. How many chickens are there, and how many rabbits? Puzzle Solution: Let c be the number of chickens, and r be the number of rabbits. r + c = … Read More →

## Nugget Numbers | Math Brain Teaser

Puzzle: At McDonald’s you can order Chicken McNuggets in boxes of 6,9, and 20. What is the largest number of nuggets that you cannot order using any combination of the above? Puzzle Solution: 43 It is possible to achieve all multiples of 3 that are bigger than 6, through the 6s and 9s alone. Adding … Read More →

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