WAP that takes an integer N from keyboard, computes and display the sum of the numbers from N to (2*N) if N is nonnegative. If N is negative then

Question

WAP that reads an integer N from keyboard, computes and display the sum of the numbers from N to (2N) if N is nonnegative. If N is negative number, then it is the sum of the number from (2n) to n. The starting and ending points are included in the sum.

Answer 1

def myfunc(n):
ls=[]

#we are going to append all the number from n to 2n
#and return their sum
#since 2n is also included, therefore end point of loop must be 2n+1

if n<0:
    for i in range(n,2*n-1,-1):
       ls.append(i)
else:
    for i in range (n,2*n+1):
        ls.append(i)
return sum(ls)