SDE - 1

You have been given an array/list 'arr' consisting of 'n' elements.

Each element in the array is either 0, 1 or 2.

Sort this array/list in increasing order.

Do not make a new array/list. Make changes in the given array/list.

Example :

Input: 'arr' = [2, 2, 2, 2, 0, 0, 1, 0]

Output: Final 'arr' = [0, 0, 0, 1, 2, 2, 2, 2]

Explanation: The array is sorted in increasing order.

Given a singly linked list of integers. Your task is to return the head of the reversed linked list.

For example:

The given linked list is 1 -> 2 -> 3 -> 4-> NULL. Then the reverse linked list is 4 -> 3 -> 2 -> 1 -> NULL and the head of the reversed linked list will be 4.

Follow Up :

Can you solve this problem in O(N) time and O(1) space complexity?

You have been given a binary tree of 'N' nodes. Print the Spiral Order traversal of this binary tree.

For example

For the given binary tree [1, 2, 3, -1, -1, 4, 5, -1, -1, -1, -1]
    1
   / \
  2   3
     / \
    4   5

Output: 1 3 2 4 5

Given an array of numbers, find the maximum sum of any contiguous subarray of the array.

For example, given the array [34, -50, 42, 14, -5, 86], the maximum sum would be 137, since we would take elements 42, 14, -5, and 86.

Given the array [-5, -1, -8, -9], the maximum sum would be -1.

Follow up: Do this in O(N) time.

Questions about scheduling algorithms, dead lock, synchronization etc. were asked.