Write a program that prompts the user to enter a social security number in the format ddd-dd-, where d is a digit. your program should check whether the input is valid.

hint: use chatat() and isdigit() methods.

ex.

input: 111-11-

output: valid ssn



input: 11-11-

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-: ");

string social = kbd_in.();

system. out. println(" you have entered: "+ social);

kbd_in. close();