The challenge

Given a two-dimensional array of integers, return the flattened version of the array with all the integers in the sorted (ascending) order.

Example:

Given [[3, 2, 1], [4, 6, 5], [], [9, 7, 8]], your function should return [1, 2, 3, 4, 5, 6, 7, 8, 9].

The solution in Python code

Option 1:

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def flatten_and_sort(array):
    a = []
    for b in array:
        for c in b:
            a.append(c)
    return sorted(a)

Option 2:

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def flatten_and_sort(array):
    return sorted([j for i in array for j in i])

Option 3:

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def flatten_and_sort(array):
    return sorted(sum(array, []))

Test cases to validate our solution

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import test
from solution import flatten_and_sort

@test.describe("Fixed Tests")
def fixed_tests():
    @test.it('Basic Test Cases')
    def basic_test_cases():
        test.assert_equals(flatten_and_sort([]), [])
        test.assert_equals(flatten_and_sort([[], []]), [])
        test.assert_equals(flatten_and_sort([[], [1]]), [1])
        test.assert_equals(flatten_and_sort([[3, 2, 1], [7, 9, 8], [6, 4, 5]]), [1, 2, 3, 4, 5, 6, 7, 8, 9])
        test.assert_equals(flatten_and_sort([[1, 3, 5], [100], [2, 4, 6]]), [1, 2, 3, 4, 5, 6, 100])