#!usr/bin/env python3
def sharq(number) :
    if number < 1 :
        return 0
    else:
        return (number + sharq(number - 2))
num = int(input("Enter the number : "))
if num < 0 :
    print ("Your number is not natural!")
else :
    print("The sum of row is equal", sharq(num))

ca51b236dd05710c708fd578fdf4dde271ccdb64
<mask token>

def sharq(number):
    if number < 1:
        return 0
    else:
        return number + sharq(number - 2)


<mask token>

def sharq(number):
    if number < 1:
        return 0
    else:
        return number + sharq(number - 2)


<mask token>
if num < 0:
    print('Your number is not natural!')
else:
    print('The sum of row is equal', sharq(num))

def sharq(number):
    if number < 1:
        return 0
    else:
        return number + sharq(number - 2)


num = int(input('Enter the number : '))
if num < 0:
    print('Your number is not natural!')
else:
    print('The sum of row is equal', sharq(num))

#!usr/bin/env python3
def sharq(number) :
    if number < 1 :
        return 0
    else:
        return (number + sharq(number - 2))
num = int(input("Enter the number : "))
if num < 0 :
    print ("Your number is not natural!")
else :
    print("The sum of row is equal", sharq(num))
