List Comprehensions (Python 3)
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# List Comprehensions (Python 3)

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. 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;. Please use list comprehensions rather than multiple loops, as a learning exercise.

• Example
• x = 1
• y = 1
• z = 2
• n = 3

All permutations of [i,j,k] are: [[0,0,0],[0,0,1],[0,0,2],[0,1,0],[0,1,1],[0,1,2],[1,0,0],[1,0,1],[1,0,2],[1,1,0],[1,1,1],[1,1,2]].

Print an array of the elements that do not sum to n = 3. [[0,0,0],[0,0,1],[0,0,2],[0,1,0],[0,1,1],[1,0,0],[1,0,1],[1,1,0],[1,1,2]].

• Input Format
• Four integers x, y, z and n, each on a separate line.
• Constraints
• Print the list in lexicographic increasing order.

#### 문제풀이

• 무언가 list comprehensions으로 풀어야할것 같지만.. 배움이 아직 짧은듯 싶다.
• i,j,k는 x,y,z보다 숫자가 작거나 같고, 그 원소들로 [i,j,k]의 리스트를 만들면 되니, for문으로 각각 append 시켜주는 코드를 생성하였다.
```1 2 3 4 5 if __name__ == '__main__': x = int(input()) y = int(input()) z = int(input()) n = int(input()) ```
```1 2 3 4 1 1 2 3 ```
```1 2 3 4 5 6 7 8 9 10 11 total_ls = [] ls = [] for i in range(x+1): for j in range(y+1): for k in range(z+1): ls.append(i) ls.append(j) ls.append(k) if sum(ls) != n: total_ls.append(ls) ls = [] ```
```1 total_ls ```
```1 2 3 4 5 6 7 8 9 [[0, 0, 0], [0, 0, 1], [0, 0, 2], [0, 1, 0], [0, 1, 1], [1, 0, 0], [1, 0, 1], [1, 1, 0], [1, 1, 2]] ```
```1 ```