[Stage 12] Sorted by Height

Some people are standing in a row in a park. There are trees between them which cannot be moved. Your task is to rearrange the people by their heights in a non-descending order without moving the trees.

Example

For a = [-1, 150, 190, 170, -1, -1, 160, 180], the output should be sortByHeight(a) = [-1, 150, 160, 170, -1, -1, 180, 190].

Input/Output

• [execution time limit] 4 seconds (py3)

• [input] array.integer a

If a[i] = -1, then the ith position is occupied by a tree. Otherwise a[i] is the height of a person standing in the i^th position.

Guaranteed constraints:
5 ≤ a.length ≤ 15, -1 ≤ a[i] ≤ 200.

[output] array.integer

Sorted array a with all the trees untouched.

def sortByHeight(a):
    b = [i for i in sorted(a) if i != -1]
    j = 0
    for i in range(len(a)):
        if a[i] != -1:
            a[i] = b[j]
            j += 1
    return a