In a grid of 4 by 4 squares you want to place a skyscraper in each square with only some clues:

The height of the skyscrapers is between 1 and 4
No two skyscrapers in a row or column may have the same number of floors
A clue is the number of skyscrapers that you can see in a row or column from the outside
Higher skyscrapers block the view of lower skyscrapers located behind them

Can you write a program that can solve this puzzle?

Example:

To understand how the puzzle works, this is an example of a row with 2 clues. Seen from the left side there are 4 buildings visible while seen from the right side only 1:

4

1

There is only one way in which the skyscrapers can be placed. From left-to-right all four buildings must be visible and no building may hide behind another building:

4

1

2

3

4

1

Example of a 4 by 4 puzzle with the solution:

	1	2

			2
1

	3

			1	2
	2	1	4	3
	3	4	1	2	2
1	4	2	3	1
	1	3	2	4
			3

Task:

Finish:

```javascript function solvePuzzle(clues) ``` ```csharp public static int[][] SolvePuzzle(int[] clues) ``` ```c int** SolvePuzzle (int *clues); ``` ```cpp int** SolvePuzzle (int *clues); ``` ```java public static int[][] solvePuzzle (int[] clues) ``` ```java def solve_puzzle (clues) ``` ```haskell solve :: [Int] -> [[Int]] ``` ```ruby def solve_puzzle(clues) ``` ```go func SolvePuzzle(clues []int) [][]int ``` ```clojure defn solve-puzzle [clues] ``` ```fsharp solvePuzzle (clues : int[]) : int[][] ```

Pass the clues in an array of 16 items. This array contains the clues around the clock, index:

	0	1	2	3
15					4
14					5
13					6
12					7
	11	10	9	8

If no clue is available, add value `0`
Each puzzle has only one possible solution
`SolvePuzzle()` returns matrix `int[][]`. The first indexer is for the row, the second indexer for the column. (Python: returns 4-tuple of 4-tuples, Ruby: 4-Array of 4-Arrays)

If you finished this kata you can use your solution as a base for the more challenging kata: 6 By 6 Skyscrapers

Kata

4 By 4 Skyscrapers

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