**Find the pivot element in an array in which elements are first in strictly decreasing and then in strictly increasing order.**

**Sort an array such that all odd numbers are in left side and sorted in increasing order where all even numbers are sorted in decreasing order and come after the odd numbers.**

**Given a list of events with start time and end time, find the events which have conflict with any other.**

**Spiral order traversal of a matrix**

**Find the nearest sibling of a given node in a tree.**

**Find minimum distance of three arrays.**

**Given a sequence, find the subsequence with maximum sum.**

**Diameter of a binary tree.**

**Find balanced Binary sub-tree of size N in Binary Tree.**

Adobe:

**Implement Binary Search using one comparison per iteration.**

**Calculate square of a number without using arithmetic operators and inbuilt methods**

**Generic Swap function in C.**

**Print paths from root to all leaves in a Binary Tree.**

**Implement doubly link list with only one address field**

**Multiply two numbers using bitwise operators**

**Find Median of infinite streams of numbers**

**Url Encode a string**

Direct I:

**Find minimum substring which contains all characters in a Set.**

Google:

**Find maximum fall in an array**

**Find nth minimum in Binary Search Tree**

**Reverse linked list without using recursion**

**Construct BST from given preorder traversal**

Pubmatic:

**Find average of all element of an array**

**Bitonic subarray with maximum length**

**Longest Bitonic subsequence**

Salesforce:

**In an unsorted array, find a pair (a, b) such that a+b = k**

**Find out elements of Array2 which are not in Array1**

**Spiral order traversal of Binary Tree**

Amazon:

**Design LRUCache**

**Add two numbers represented by linked lists**

**Best time buy sell stock**

**Implement queue using stacks**

**Run Length Encoding**

**Given an array of 0 and 1, find out longest subarray with equal number of 0 and 1.**

**Find number of vertical lines that can cover whole nodes of Binary Tree**

**Set inorder successor of each nodes of Binary Tree**

**Flatten a multilevel linked list**

**Find the first occurrence of an integer in an array**

**Convert a binary tree to a tree that holds children sum tree**

**Reverse a Linked List in groups of given size**

Informatica:

**Given a transaction log in which each line contains a transaction detail (Customer Id, Customer name, Price), Find out the average price given by a customer**

Infibeam:

**Implement T9 Dictionary**

**Reverse Level Order Traversal of Binary Tree**

Thought Works:

**Implement Game of Life**

**MAZ Digital:**

**Push, Pop, FindMin in O(1) without extra space**

SAP Labs:

**Move all zeroes to end of array**

Flipkart:

**Find the minimum window in a large string which contains all characters of another string.**

**Clone a linked list with next and random pointer**

**Find fixed point in array**

Synopsys:

**Find the maximum sum in an array such that no two elements are adjacent**

**Check if any two intervals overlap among the given n intervals**

**Sort array which contains only 0 and 1**

**Carwale:**

**Find a triplet in an array that sum to given value**

**Paytm:**

**Coin change problem**

**Minimum distance between two numbers in an array**

**OLA:**

**Modify Boolean matrix**