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"""
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.
"""

import itertools

def isPalindrome(x):
    """Checks if x is a palindrome. Returns true or false."""
    return str(x) == str(x)[::-1]
    
    """
    This is my old solution. I'm sorry. 
    
    a = str(x)
    l = len(a)
    hl = l/2
    i = 0
    if l%2 ==0:
        # print("even")
        while (i < hl):
            # print(i)
            # print(l-i-1)
            if a[i] != a[l-i-1]:
                # print("not palindrome")
                return(0)
                # break
            i = i+1
        return(1)
    else:
        # print("odd")
        while (i < hl):
            # print(i)
            # print(l-i-1)
            if a[i] != a[l-i-1]:
                # print("not palindrome")
                return(0)
                # break
            i = i+1
        return(1)
    """
    
def findMaxPalindrome(maxNum):
    """Returns highest palindrome from all possible products of numbers up to maxNum."""
    combinations = itertools.combinations(range(maxNum),2) # all possible multiplier combinations within range
    products = []
    for y in combinations:
        prod = y[0]*y[1]
        if(isPalindrome(prod)):
            products.append(prod) # all possible products in range
    return(max(products))


    

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findMaxPalindrome(999)


    

    
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906609

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