Flatten a 2D Array

Combine the rows of a 2D integer array into one array. Read rows from top to bottom and integers within each row from left to right. Skip empty rows. Preserve repeated integers and their order. Rows may have different lengths. There are exactly two array levels: rows contain only integers, with no null values or deeper lists.

Implement flatten_nested_list(values).

Input

values: The integer rows to combine, in order.

Output

Return all integers in row order. Return an empty array if there are no integers.

Ограничения

0 ≤ number of rows ≤ 10,000. At most 10,000 integers in total. Each integer is between −1,000,000,000 and 1,000,000,000. Rows may be empty or have different lengths.

Примеры

Ввод:
values = [
    [1, 2],
    [],
    [3, 4]
]

Ожидаемый вывод:
expected = [1, 2, 3, 4]

Ввод:
std::vector<std::vector<long long>> values = {
    {1, 2},
    {},
    {3, 4}
};

Ожидаемый вывод:
std::vector<long long> expected = {1, 2, 3, 4};

Ввод:
long[][] values = new long[][] {
    new long[] {1, 2},
    new long[] {},
    new long[] {3, 4}
};

Ожидаемый вывод:
long[] expected = new long[] {1, 2, 3, 4};

Ввод:
values = [
    [],
    []
]

Ожидаемый вывод:
expected = []

Ввод:
std::vector<std::vector<long long>> values = {
    {},
    {}
};

Ожидаемый вывод:
std::vector<long long> expected = {};

Ввод:
long[][] values = new long[][] {
    new long[] {},
    new long[] {}
};

Ожидаемый вывод:
long[] expected = new long[] {};

Ссылки

Это задание адаптировано для CodeUtility. Следуйте условию и ограничениям выше.

• Exercism: Flatten Array