Условие
Sort the values into ascending order. For an odd number of values, take the middle one. For an even number, take the arithmetic mean of the two middle values. This challenge accepts only nonempty lists.
Implement median_number(numbers).
Input
numbers: The nonempty list of values.
Output
Return the median as a number; it may end in .5.
Ограничения
1 ≤ list length ≤ 100,000. Each value is an integer between −1,000,000,000 and 1,000,000,000.
Примеры
Ввод:
numbers = [2, 8, 4, 10]
Ожидаемый вывод:
expected = 6.0Ввод:
std::vector<long long> numbers = {2, 8, 4, 10};
Ожидаемый вывод:
double expected = 6.0;Ввод:
long[] numbers = new long[] {2, 8, 4, 10};
Ожидаемый вывод:
double expected = 6.0;Пояснение
Sorted order is 2, 4, 8, 10. The middle pair averages to (4 + 8) / 2 = 6.
Ввод:
numbers = [9, 1, 4]
Ожидаемый вывод:
expected = 4.0Ввод:
std::vector<long long> numbers = {9, 1, 4};
Ожидаемый вывод:
double expected = 4.0;Ввод:
long[] numbers = new long[] {9, 1, 4};
Ожидаемый вывод:
double expected = 4.0;Пояснение
Sorted order is 1, 4, 9, whose middle value is 4.
Как подступиться
Сначала попробуйте сами, затем открывайте подсказки по одной.
Подсказка 1
The median depends on sorted order, so the positions in the sorted list are what matter.
Подсказка 2
After sorting, use the middle element for odd length, or combine the two middle elements for even length.
Подсказка 3
Be careful to preserve halves when averaging two middle values, since the answer may end in .5.
Ожидаемая сложность
O(n log n) time, O(n) extra space
Ссылки
Это задание адаптировано для CodeUtility. Следуйте условию и ограничениям выше.