Read a $2-$character string from input into variable inString. Declare a Boolean variable isValid and assign isValid with true if the following conditions are met:

instring does not contain two of the same character.

For alphabetic characters, inString does not contain two of the same letter $($regardless of case$).$

Otherwise, assign is Valid with false

Ex$.$ If the input is $4^{{?}^{{?}^{?}}},$ then is Valid is assigned with true, so the output is:

Valid string

Ex$.$ If the input is $Rr,$ then is Valid is assigned with false, so the output is:

Invalid string

Note: Use instring $=scnr*$ nextIine $()$ to read the entire line from input into inString.

import java.util.scanner;

public class Stringchecker $\{$

public static void main$($String$[]$ args$)\{$

Scanner scnr $=$ new Scanner$($

System.in$)$;

String instring;

$Y^{**}$ Your code goes here $*/$

if $($isvalid$)\{$

$\}$

System.out.println$("$Valid string"$)$;

else $\{$

System.out.println$("$Invalid string"$)$: