import java.util.Scanner;

public class TASK3 {

public static void main(String[] args) {

int num,n=0;

Scanner kb = new Scanner(System.in);

do {

System.out.println("enter an integer >= 1 ");

num= kb.nextInt();

if(num

System.out.println("Error: invalid input ! ");

}while (num

while( num != 0 )

{

n = n * 10;

n = n + num%10;

num = num/10;

}

System.out.println("the integer entered is"+num+","+"its reverse is:"+n);

}

}

why i get 0

enter an integer = 1 653 the integer entered is e,its reverse 1s:358