L3 Engineer

Given an array of integers ‘A’, and an integer ‘K’ find the number of happy elements.

Element ‘X’ is happy if there exists at least 1 element whose difference is less than ‘K’ i.e. an element ‘X’ is happy if there is another element in the range [X-K, X+K] other than ‘X’ itself.

For Example:

If N=3 and K=1 and array elements are [1,2,5]. 

For A[0], A[1] is the element that lies in the range [0,2] so, A[0] is the happy element.
For A[1], A[0] is the element that lies in the range [1,3] so, A[1] is the happy element.
For A[2], there is no element that lies in the range [4,6] other than A[2] so, A[2] is not the happy element.

Hence, the output will be 2.

You are given a string ‘S’ of size ‘N’ where ’S’ contains only characters ‘0’ and ‘1’. Your task is to divide ‘S’ into ‘K’ contiguous substrings such that the following conditions hold true :

1. Let ‘X’ be a binary number formed by reading a substring of ‘S’ from left to right.
2. ‘X’ must not contain leading zeroes.
3. The decimal equivalent of ‘X’ must be a power of 5.
4. K must be the minimum possible.

Note :

If no such ‘K’ possible, then you need to return -1. 

Your task is to maintain a data structure that supports the following functions of a web browser.

1- Browser(homepage): Set homepage of the browser

2- Visit(url): Visit the url from the current page. It clears up all the forward history.

3- Back(steps): Move ‘steps’ backward in the browser history

4- Forward(steps): Move ‘steps’ forward in the browser history

Note:

If you can’t move steps forward or backward, just return the last website that can be reached.

The Queries are in the given format-:
The first line of each query contains the string representing the homepage of the web browser.

(1, url): Visit the url from the current page. 

(2, steps): Move ‘steps’ backward in the browser history.

(3, steps): Move ‘steps’ forward in the browser history.

For example:

You are queries as  [[“homepage.com”], [1 , “facebook.com”], [1, “codingninjas.com”],[2, 1], [3, 1]]
1 query is the query that sets the homepage as “homepage.com”.
2 query is the query to visit “facebook.com”
3 query is the query to visit “codingninjas.com”
4 query is the query that moves back one step to “facebook.com”
5 query is the query that moves forward one step to “codingninjas.com”

Hence the answer is [“facebook.com”, “codingninjas.com”]

You have been given an array/list ‘ARR’ of integers consisting of ‘N’ integers. You are also given a size ‘M’. You need to display the median of all the subarrays of size ‘M’ and it is starting from the very left of the array.

Median is the middle value in an ordered integer array/list. If the size of the array/list is even there is no middle element. So the median is the mean of two middle values in an even size array/list.

Your task is to return the median of all the subarrays whose size is ‘M’.

Example:

Let’s say you have an array/list [1,4,3,5] and ‘M’ is 3.Then the first subarray of size 3 is [1,4,3] whose median is 3.Then the second subarray of size 3 is [4,3,5] whose median is 4. Therefore the median of all the subarrays of size 3 is [3.0,4.0].