def main():
    input()
    values = [int(i) for i in input().split()]
    sorted_values = sorted(values)
    value_num = len(values)
    if value_num % 2 == 0:
        mid_index = value_num // 2
        mid = (sorted_values[mid_index - 1] + sorted_values[mid_index]) / 2
        print(mid)
    else:
        mid_index = value_num // 2
        mid = sorted_values[mid_index]
        print(mid)


if __name__ == '__main__':
    main()