Медиана массива неизвестной длины

import math
 
with open("input.txt", 'r') as file:
    a = int(file.readline())
    b = list([int(i) for i in file.readline().split(' ')])
    pr1 = sum(b) / a
    if pr1 % 1 == 0:
        with open("output.txt", "w") as file1:
            file1.write(str(round(pr1)))
    else:
        with open('output.txt', 'w') as file1:
            file1.write(str(math.floor(pr1)) + ' ')
            file1.write(str(math.ceil(pr1)))

fin = open("input.txt")
fout = open("output.txt", "w")
n = int(fin.readline())
b = list([int(i) for i in fin.readline().split()])
if n%2:
    fout.write(str(round(sum(b)/n)))
else:
    fout.write(str(round(sum(b[:n//2])/(n//2))) + ' ' + str(round(sum(b[n//2:])/(n//2))))
fin.close()
fout.close()

fin = open("input.txt")
fout = open("output.txt", "w")
n = int(fin.readline())
b = sorted(list([int(i) for i in fin.readline().split()]))
if n%2:
    fout.write(str(round(sum(b)/n)))
else:
    fout.write(str(b[n//2-1]) + ' ' + str(b[n//2]))
fin.close()
fout.close()

fin = open("input.txt")
fout = open("output.txt", "w")
n = int(fin.readline())
b = sorted(list([int(i) for i in fin.readline().split()]))
if n%2:
    fout.write(b[n//2]))
else:
    fout.write(str(b[n//2-1]) + ' ' + str(b[n//2]))
fin.close()
fout.close()

fin = open("input.txt")
fout = open("output.txt", "w")
n = int(fin.readline())
b = sorted(list([int(i) for i in fin.readline().split()]))
if n%2:
    fout.write(str(b[n//2]))
else:
    fout.write(str(b[n//2-1]) + ' ' + str(b[n//2]))
fin.close()
fout.close()