Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Python Python Basics (2015) Number Game App Squared

Can't multiply sequence with non-int 'str'

Write a function named squared that takes a single argument. If the argument can be converted into an integer, convert it and return the square of the number (num ** 2 or num * num). If the argument cannot be turned into an integer (maybe it's a string of non-numbers?), return the argument multiplied by its length. Look in the file for examples.

squared.py
# EXAMPLES
def squared(num):
    try:
        int(num)
    except ValueError:
        return num * len(num)
    else:
        return num * num
# squared(5) would return 25
# squared("2") would return 4
# squared("tim") would return "timtimtim"

1 Answer

Steven Parker
Steven Parker
231,236 Points

You're close, but...

def squared(num):
    try:
        int(num)          # this tests the conversion, but doesn't store the number anywhere
    except ValueError:
        return num * len(num)
    else:
        return num * num  # this tries to multiple the original argument (maybe a string?)

def squared(num): try: a = int(num) except ValueError: return num * len(num) else: return a * 2

Still doesnt work!

Steven Parker
Steven Parker
231,236 Points

But "a * 2" is just "a times 2", not "a squared". For that you'd need "a ** 2" or "a * a"