Question

(Python)

Implement a function to compute a sum that can compute sum for an arbitrary number of input integers or float numbers. In other words, calls like this should all work:

flexible_sum(x1, x2) # sum of two integer or float numbers or strings x1 and x2

flexible_sum(x1, x2, x3) # sum of 3 input parameters

and can also handle a single input parameter, returning it unchanged and with the same type, i.e.:

  flexible_sum(1)

returns 1

and can accept an arbitrary number of strings as input parameters and return their concatenation. In other words, the following call

  flexible_sum('one ', 'two ', 'three ')

should give result string

  'one two three '

And the function can also accept a single input parameter in the form of a list of an arbitrary length and return a sum for it.

If you can, try to implement your function without calls to any other external functions, including Python built-in functions.

Answer 1

def flexible_sum(*args):

    s = ''
    c = 0
    l =[]
    if len(args) == 1:       #it the args has length 1 it is either a list or just a single value
        for i in args:
            l = i
        if isinstance(l,list):     #isinstance is used to check if the parameter is list
            for i in l:
                c += i
            return c
        else:
            return l
    elif  isinstance(args[1], str):    #isinstace is used to check if the parameter is string
        for i in args:
            s+=i
        return s
    else:
        for i in args:
            c+=i
        return c


print(flexible_sum(1))                  #taking one parameter
print(flexible_sum(2,3,4))              #taking three int as parameter
print(flexible_sum(1.2,4.6,7.9))        #taking three float as parameter
print(flexible_sum([1,2,3,4,5]))        #taking a list as parameter
print(flexible_sum('one ','two ','three '))         #taking strings as parameter

output: