Write a program that prompts the user to enter a Social Security Number in the format DDD-DD-DDDD, where D is a digit. Your program should check whether the input is valid.

HINT: Use chatAt() and isDigit() methods.

EX.

INPUT: 111-11-1111

OUTPUT: Valid SSN

---------------------------

INPUT: 11-11-1111

OUTPUT: Invalid SSN

******* I know that I can solve this problem by looping through the characters of the string in the SSN but I want to make the code I wrote beneath work. I am having a problem on my second to last if- statement. In that statement it says that all of my variables d1-d9 "cannot be resolved to variable." I initially thought that this might be a problem with scope of my variables but I dont belive it is. Why am I getting an error and what can I do to make this code work ???*********

import java.util.Scanner;

public class CheckSSN {

public static void main(String [] args) {

Scanner kbd_in = new Scanner(System.in);

System.out.print(" Enter your social security numer in the format DDD-DD-DDDD: ");

String social = kbd_in.nextLine().trim();

System.out.println(" You have entered: "+ social);

kbd_in.close();

//Test to see if length is correct

boolean properLength;

if (social.length() !=11) {

properLength = false;

}else {

properLength = true;

}

//Test to see if dashes are in the correct place

boolean properDash;

if((social.charAt(4)!='-')&&(social.charAt(7)!='-')) {

properDash = false;

}else {

properDash = true;

}

//Variables d1-d9 will hold a T/F depending on wether or not the value

//is an integer.

if(properLength == true) {

boolean d1 = Character.isDigit(social.charAt(social.length()-11));

boolean d2 = Character.isDigit(social.charAt(social.length()-10));

boolean d3 = Character.isDigit(social.charAt(social.length()-9));

boolean d4 = Character.isDigit(social.charAt(social.length()-7));

boolean d5 = Character.isDigit(social.charAt(social.length()-6));

boolean d6 = Character.isDigit(social.charAt(social.length()-4));

boolean d7 = Character.isDigit(social.charAt(social.length()-3));

boolean d8 = Character.isDigit(social.charAt(social.length()-2));

boolean d9 = Character.isDigit(social.charAt(social.length()-1));

}

// Testing if all of d1-d9 are actually digits

boolean properDigits;

if((d1 == true) && (d2 == true) && (d3 == true) && (d4 == true)

&& (d5 == true) && (d6 == true) && (d7 == true) && (d8==true)

&& (d9==true)) {

properDigits = true;

}else {

properDigits = false;

}

//If dashes are in proper place, we have the proper length, and d1-d9 are

//integers, then we have a valid input

if((properLength == true)&&(properDash==true)&&(properDigits==true)) {

System.out.println(" Valid Input ");

}else {

System.out.println(" Invalid Input ");

}

}

}