list_comprehensions.py

"""
List Comprehensions

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. 
Here, 0 <= i <= X; 0 <= j <= Y; 0 <= k <= Z 

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:
1
1
1
2

Sample Output:
[[0, 0, 0], [0, 0, 1], [0, 1, 0], [1, 0, 0], [1, 1, 1]]

Explanation:
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.
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:
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 )]


@author: Luísa Maria Mesquita
"""

def list_comprehensions():
    x = int(input("X: "))
    y = int(input("Y: "))
    z = int(input("Z: "))
    n = int(input("N: "))
    
    result = [[i,j,k] for i in range(0, x+1) for j in range(0, y+1) for k in range(0,z+1) if(i+j+k != n)]
    
    print(result)