4: Largest palindrome product

Description

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.

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Your Solution

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def problem4(N): # N = number of digits
    # Try your solution here
    return solution

# Testing:
unittest.main(argv=[''], verbosity=2,exit=False)

# Printing Project Euler Solution
# print(problem4(3))

My solution

Spoiler Alert!!

See my solution bellow

# Note: this solution does not scale well! Keep N<=4
def problem4(N):
    palindromic = 0
    for i in range(10**N-1, 10**(N-1)-1, -1):
        for j in range(10**N-1, i-1, -1):
            product = i*j
            if str(product) == str(product)[::-1]:
                if product > palindromic:
                    palindromic = product
                    break
    return palindromic

# Testing
unittest.main(argv=[''], verbosity=2,exit=False)

The largest palindrome made from the product of two 3-digit numbers is

# Printing Project Euler Solution
problem4(3)

906609