How to avoid the semantic error in Python?

Question

My homework is about Fermat's Last Theorem:

1) Write a function named check_fermat that takes four parameters—a, b, c and n—and checks to see if Fermat’s theorem holds.

2) Write a function that prompts the user to input values for a, b, c and n, converts them to integers, and uses check_fermat to check whether they violate Fermat’s theorem.

Here is my code as follows. It works. However, there is always a "None" following the correct answer, such as "Correct! None".

It would be appreciated if you could help me with the problem. Thank you so much.

def check_fermat(a,b,c,n):
    if n > 2:
        print("“Holy smokes, Fermat was wrong!")
    if n == 2  and a**n + b**n == c**n:
        print("Correct!")    
    else:
        print("No, that doesn’t work")


def check_number():
    a = int(input("Choose a number for a: "))
    b = int(input("Choose a number for b: "))
    c = int(input("Choose a number for c: "))
    n = int(input("Choose a number for n: "))
    print(check_fermat(a,b,c,n))

check_number()

`print(check_fermat(a,b,c,n))` prints the None, since `check_fermat` is returning None, just do `check_fermat(a,b,c,n)` — Devesh Kumar Singh, Jun 24 '19 at 15:05
You may also want to look at https://stackoverflow.com/q/3881434 and its duplicates and related questions. — mercator, Jun 24 '19 at 15:09
Or better, make the function return a string. But I am afraid your function has worse problems than that. — Stop harming Monica, Jun 24 '19 at 15:11

score 0 · Answer 1 · answered Jun 24 '19 at 15:06

print(check_fermat(a,b,c,n))

This line is what prints None, this is because the return value of check_fermat is None.

The solution is either:

only print in check_fermat, remove print from print(check_fermat(a,b,c,n))
OR, return a string (or some other sensible return value) from check_fermat, and leave print(check_fermat(a,b,c,n)) as it is.

How to avoid the semantic error in Python?

1 Answers1