test.py

# Enter your code here. Read input from STDIN. Print output to STDOUT
def get_midpoint(arr):
    return int(len(arr) / 2)

def find_median(arr):
    if len(arr) % 2 != 0:
        mid_point = get_midpoint(arr)
        return round(arr[mid_point], 1)
    else:
        top_middle = (len(arr) / 2)
        bottom_middle = (len(arr) / 2) - 1
        return round((arr[top_middle] + arr[bottom_middle]) / 2, 1)

def get_halves(arr):
    halves = []
    midpoint = get_midpoint(arr)
    if len(arr) % 2 != 0:
        arr.pop(midpoint)
    lower_half = arr[:midpoint]
    upper_half = arr[midpoint:]
    halves.append(lower_half)
    halves.append(upper_half)
    return halves


if __name__ == '__main__':
    _ = input()
    arr = [int(x) for x in input().split(' ')]
    freq = [int(x) for x in input().split(' ')]
    new_arr = [[x] * y for x, y in zip(arr, freq)]
    new_arr.sort()
    flat_arr = [x for sub_arr in new_arr for x in sub_arr]
    print(flat_arr)
    lower_half, upper_half = get_halves(flat_arr)
    q1 = find_median(lower_half)
    q3 = find_median(upper_half)
    print((q3 - q1))