List Comprehensions

a, b, c, n = [int(input()) for _ in range(4)]

1
2
3
4

print ([[x,y,z] for x in range(a + 1) for y in range(b + 1) for z in range(c + 1) if x + y + z != n])

[[0, 0, 0], [0, 0, 1], [0, 0, 2], [0, 0, 3], [0, 1, 0], [0, 1, 1], [0, 1, 2], [0, 2, 0], [0, 2, 1], [0, 2, 3], [1, 0, 0], [1, 0, 1], [1, 0, 2], [1, 1, 0], [1, 1, 1], [1, 1, 3], [1, 2, 0], [1, 2, 2], [1, 2, 3]]