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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
230,995 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
230,995 Points

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