SDE - 2

You are given 'N' rectangular buildings in a 2-dimensional city. Your task is to compute the skyline of these buildings, eliminating hidden lines return the skyline formed by these buildings collectively. A city's skyline is the outer contour of the silhouette formed by all the buildings in that city when viewed from a distance. The geometric information of each building is given in the array of buildings where BUILDINGS[i] = [LEFT_i, RIGHT_i, HEIGHT_i]:

-> LEFT_i is the x coordinate of the left edge of the ith building.

-> RIGHT_i is the x coordinate of the right edge of the ith building.

-> HEIGHT_i is the height of the ith building.

You may assume all buildings are perfect rectangles grounded on an absolutely flat surface at height 0.

The skyline should be represented as a list of "key points" sorted by their x-coordinate in the form [[x1, y1], [x2, y2], ...]. Each key point is the left endpoint of some horizontal segment in the skyline except the last point in the list, which always has a y-coordinate 0 and is used to mark the skyline's termination where the rightmost building ends. Any ground between the leftmost and rightmost buildings should be part of the skyline's contour.

Note:

There must be no consecutive horizontal lines of equal height in the output skyline. For instance, [...,[2 3], [4 5], [7 5], [11 5], [12 7],...] is not acceptable; the three lines of height 5 should be merged into one in the final output.

As such: [..., [2 3], [4 5], [12 7],...]. 

Also, the buildings are sorted by a non-decreasing order.

For more clarification see sample case 1.

You are a student of Netaji Subhas Institute of Technology. You have to take ‘N’ number of courses labelled from 1 to N to complete your B.Tech Degree.

Some courses may have prerequisites, for example, to take course 1 you have to first take course 2, which is expressed as a pair: [1, 2]. Now, your task is to find is it possible for you to finish all courses.

Note: There are no duplicate pairs in the prerequisites array.

For example-

If N = 2 and prerequisite = [[1, 2]]. Then, there are a total of 2 courses you need to take. To take course 1 you need to finish course 2. So, it is possible to complete all courses. 

Given an array/list of integers of length ‘N’, there is a sliding window of size ‘K’ which moves from the beginning of the array, to the very end. You can only see the ‘K’ numbers in a particular window at a time. For each of the 'N'-'K'+1 different windows thus formed, you are supposed to return the maximum element in each of them, from the given array/list.

You are given a two-dimensional grid having 'N' rows and 'M' columns, consisting of upper case characters. You are also given a word 'WORD'. You have to find the number of occurrences of that word in the grid.

Starting from a given cell, a word can be formed by moving in all eight directions: horizontally left, horizontally right, vertically up, vertically down, and four diagonal directions.

Example :

There are three occurrences of the word 'NINJA' in the following grid:

Note :

1) Given word will not be a single character.

2) If occurrences of the given word start from two different cells, then these two occurrences are considered to be different.

Consider the word 'XYX' to be searched in the string 'AXYXB'. Here, we find an occurrence of 'XYX' at index 2 going in the right direction, and another occurrence at index 4 going in the left direction.

Although these two words correspond to the same word, they will be considered as different occurrences.

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