SDE - Intern

You are given an array ‘arr’ that contains an equal number of positive and negative elements. Rearrange the given array such that positive and negative numbers are arranged alternatively. Also, the respective relative order of positive and negative should be maintained.

For example:

For the given arr[ ] = { -1, 3, 5, 0, -2, -5 } 
arr[ ] = {3, -1, 5, -2, 0, -5 } is valid rearrangement.
arr[ ] = {3, -1, 0, -2, 5, -5 } is invalid rearrangement; order of 0 and 5 is changed. 
arr[ ] = {3, -1, 5, 0, -2, -5 } is invalid rearrangement; positive and negative elements are not alternative.

Note:

Make changes in the same array and no returning or printing is needed.
Consider zero(0) as a positive element for this question.
It is guaranteed that an answer always exists.

Given two variables ‘X’ and ‘Y’. Your task is to swap the number without using a temporary variable or third variable.

Swap means the value of ‘X’ and ‘Y’ must be interchanged. Take an example ‘X’ is 10 and ‘Y’ is 20 so your function must return ‘X’ as a 20 and ‘Y’ as a 10.

You are given a Singly Linked List of integers. Return true if it has a cycle, else return false.

A cycle occurs when a node's next points back to a previous node in the list.

Example:

In the given linked list, there is a cycle, hence we return true.

You have given 7 apples. Out of the, 1 defect. You are given a weighing machine. You have to tell the minimum iteration in which you can find the defective one.