Related Tags

euler
problem
palindrome
lagest palindrome
product

# Project Euler problem 4: Largest palindrome product Educative Answers Team

In this problem, you have to calculate the largest palindrome number that can be made from​ the product of two n-digit integers. ## Algorithm

• Calculate the upper and lower bound (i.e., for n = 2, lowerBound = 10 and upperBound = 99 )
• Search for the highest product palindrome in reverse order (i.e., start a loop from 99 * 99 )
• Check whether or not each product is a palindrome.

## Code

# Python Implementation

# function
def PalindromeProductNumber(n):

upperBound = 0
lowerBound = 0
# Calculating upper bound
for i in range(1, n+1):

upperBound =upperBound * 10
upperBound =upperBound + 9

# Calculating lower bound
lowerBound = 1 + lowerBound//10

max_prdt = 0
for i in range(upperBound,lowerBound-1, -1):
for j in range(i,lowerBound-1,-1):
# calculating products in a range
product = i * j
if (product < max_prdt):
break
number = product
reverse_num = 0
# checking whether a number is palindrome
while (number != 0):

reverse_num = reverse_num * 10 + number % 10
number =number // 10
# updating product
if (product == reverse_num and product > max_prdt):
max_prdt = product

return max_prdt

n = 2
print(PalindromeProductNumber(n))


RELATED TAGS

euler
problem
palindrome
lagest palindrome
product 