Write a program in Java to display the largest four-digit even palindromic number.
Answers
Answer:
// Java problem to find out the
// largest palindrome number
// which is product of two
// n digit numbers.
class GFG
{
// Function to calculate largest
// palindrome which isproduct of
// two n-digits numbers
static int larrgestPalindrome(int n)
{
int upper_limit = 0;
// Loop to calculate upper bound
// (largest number of n-digit)
for (int i=1; i<=n; i++)
{
upper_limit *= 10;
upper_limit += 9;
}
// largest number of n-1 digit.
// One plus this number
// is lower limit which is
// product of two numbers.
int lower_limit = 1 + upper_limit / 10;
// Initialize result
int max_product = 0;
for (int i = upper_limit; i >= lower_limit; i--)
{
for (int j = i; j >= lower_limit; j--)
{
// calculating product of two
// n-digit numbers
int product = i * j;
if (product < max_product)
break;
int number = product;
int reverse = 0;
// calculating reverse of product
// to check whether it is
// palindrome or not
while (number != 0)
{
reverse = reverse * 10 + number % 10;
number /= 10;
}
// update new product if exist and if
// greater than previous one
if (product == reverse && product > max_product)
max_product = product;
}
}
return max_product;
}
// Driver code
public static void main (String[] args)
{
int n = 2;
System.out.print(larrgestPalindrome(n));
}
}