from random import shuffle
from time import time

n = 10**5
randList = [x for x in range(1, n + 1)]
helper_list = [0 for x in range(n + 1)]
shuffle(randList)


def main():
    a = 0
    b = len(randList) - 1

    start_time = time()
    sort(a, b)
    end_time = time()

    final_time = end_time - start_time
    print(final_time, "s")


def sort(a, b):
    if a == b:
        return
    k = (a + b) // 2
    sort(a, k)
    sort(k + 1, b)
    merge(a, k, k + 1, b)


def merge(a1, b1, a2, b2):

    a = a1
    b = b2

    for x in range(a, b + 1):
        if a2 > b2 or (a1 <= b1 and randList[a1] <= randList[a2]):
            helper_list[x] = randList[a1]
            a1 += 1
        else:
            helper_list[x] = randList[a2]
            a2 += 1

    for x in range(a, b + 1):
        randList[x] = helper_list[x]


if __name__ == "__main__":
    main()