## HackerRank List Comprehensions solution in Python

Let's learn about list comprehensions! You are given three integers X, Y and Z representing the dimensions of a cuboid along with an integer N. You have to print a list of all possible coordinates given by (i,j,k) on a 3D grid where the sum of (i+j+k) is not equal to N.

**Input Format**

Four integers X, Y, Z and N each on four separate lines, respectively.

**Constraints**

Print the list in lexicographic increasing order.

**Sample Input 0**

1

1

1

2

**Sample Output 0**

[[0, 0, 0], [0, 0, 1], [0, 1, 0], [1, 0, 0], [1, 1, 1]]

**Explanation 0**

*Concept*

You have already used lists in previous hacks. List comprehensions are an elegant way to build a list without having to use different for loops to append values one by one. This example might help.

**Example:** You are given two integers x and y . You need to find out the ordered pairs ( i , j ) , such that ( i + j ) is not equal to n and print them in lexicographic order.( 0 <= i <= x ) and ( 0 <= j <= y) This is the code if

**.**

*we dont use list comprehensions in Python*`python x = int ( raw_input()) y = int ( raw_input()) n = int ( raw_input()) ar = [] p = 0 for i in range ( x + 1 ) : for j in range( y + 1): if i+j != n: ar.append([]) ar[p] = [ i , j ] p+=1 print ar`

Other smaller codes may also exist, but using list comprehensions is always a good option. *Code using list comprehensions:*

`python x = int ( raw_input()) y = int ( raw_input()) n = int ( raw_input()) print [ [ i, j] for i in range( x + 1) for j in range( y + 1) if ( ( i + j ) != n )]`

**Sample Input 1**

2

2

2

2

** Sample Output 1**[[0, 0, 0], [0, 0, 1], [0, 1, 0], [0, 1, 2], [0, 2, 1], [0, 2, 2], [1, 0, 0], [1, 0, 2], [1, 1, 1], [1, 1, 2], [1, 2, 0], [1, 2, 1], [1, 2, 2], [2, 0, 1], [2, 0, 2], [2, 1, 0], [2, 1, 1], [2, 1, 2], [2, 2, 0], [2, 2, 1], [2, 2, 2]]

## Solution in Python3

```
x,y,z,n = [int(input()) for i in range(4)]
print([[i,j,k] for i in range(x+1) for j in range(y+1) for k in range(z+1) if ((i+j+k) != n)])
```