Java - Do While Statement

import java.io.*;

class ssvdowhile
 {
   public static void main(String arg[]) throws IOException
    {
      String t;
      int c,n;
      c=0;

      DataInputStream dr = new DataInputStream(System.in);

      System.out.print("Enter a whole Number : ");
      t = dr.readLine();
      n = Integer.parseInt(t);

    do{
         n = n/10;
         c = c+1;
       }while(n != 0);

      System.out.println("\nThe given Number is a " + c + " Digit Number");
   }
 }