Project Euler: Problem 4

https://projecteuler.net/problem=4

A palindromic number reads the same both ways. The largest palindrome made from the product of two 2-digit numbers is 9009 = 91 × 99.

Find the largest palindrome made from the product of two 3-digit numbers.


In [13]:
def test_if_palindrome(x):
    return str(x) == str(x)[::-1]

In [16]:
def test_3digit_products(a):
    largest_palindrome = 1
    for b in range(a,1,-1):
        if b * a <= largest_palindrome:
            break
        for c in range(a,b-1,-1):
            if b * c <= largest_palindrome: 
                break
            if test_if_palindrome(b*c):
                largest_palindrome = b*c
    return largest_palindrome

In [17]:
print(test_3digit_products(999))


906609

In [ ]:
# This cell will be used for grading, leave it at the end of the notebook.