Question

write a program in Java to display all the four digit palindromic prime numbers

Answer 1

Here's the code for the program. The description is given as comments. Copy the code into a suitable IDE, so that comments and code will be visible properly.



public class Palindrome_Number              //Creating Class
{
    public static void main(String[] args)      //Creating main() function
    {
        int p,r,d,n;            //Some int variables
        
        System.out.println("The four digit palindrome numbers are: \n");
        
        for(n=1000;n<=9999;n++)     //This loop considers all four digit numbers, as n = 1000 to 9999
        {
            p=n;                //Storing value of n into p. All calculations will be performed on p.
            r=0;                //r will contain the reverse of n
            do
            {
                d=p%10;         //Extracting digit of p onto d
                r=r*10 + d;     //Placing the digit d into appropriate place in r
                p=p/10;            
            }
            while (p!=0);

            if (r==n)           //Checking if reverse of n is equal to n
                System.out.println(n);      //Printing palindrome number
        }
    }
}