SDE - 1

You are given an array 'ARR' consisting of 'N' non-negative integers, your task is to copy the elements of 'ARR' into another array 'COPY_ARR' in reverse order.

For example:

If 'ARR' contains the following elements [ 1, 2, 3, 4, 5 ], then you should return another array that is equal to [ 5, 4, 3, 2, 1].

Given two arrays ‘ARR’ and ‘BRR’ of size ‘N’ and ‘M’ respectively. Your task is to sort the elements of ‘ARR’ in such a way that the relative order among the elements will be the same as those are in ‘BRR’. For the elements not present in ‘BRR’, append them in the last in sorted order.

For example

Consider the arrays as ARR = { 9, 5, 8, 4, 6, 5 } and BRR = { 8, 4, 5 }
The output for the above example  is { 8, 4, 5, 5, 6, 9 }.

Note:

Elements of ‘BRR’ are non repeating.

Given N pairs of parentheses, write a function to generate and print all combinations of well-formed parentheses. That is, you need to generate all possible valid sets of parentheses that can be formed with a given number of pairs.

You have been given a board where there are '2' rows and 'N' columns. You have an infinite supply of 2x1 tiles, and you can place a tile in the following ways:

1. Horizontally as 1x2 tile
2. Vertically as 2x1 tile

Count the number of ways to tile the given board using the available tiles.

Note :

The number of ways might be large so output your answer modulo 10^9 + 7.

Here an example of tile and board for 'N' = 4 :

You have been given ‘N’ houses, each house can be painted with any of three colours: green, red and yellow. You are also given a “cost” matrix of ‘N’ * 3 dimension which represents the cost of painting an i-th house (0-th based indexing) with j-th colour. The colour code is as follows: green - 0, red - 1 and yellow - 2. Now, you are supposed to find the minimum cost of painting all houses such that no adjacent houses are painted with the same colour.