Why am I having a error on line $1$:

ResturantItem.java:

public class ResturantItem implements Comparable $\{$

$//$ declare variable

private String Menu;

private double Prices;

$//$ constructor

public ResturantItem$($String Menu, double Prices$)\{$

this.Menu $=$ Menu;

this.Prices $=$ Prices;

$\}$

$//$ compareto Method for compare the menu attribute

@Override

public int compareTo$($ResturantItem o$)\{$

int menuComparsion $=$ this.Menu.compareToIgnoreCase$($o$.$Menu$)$;

if $($menuComparsion $!=0)\{$

return Integer.compare$($menuComparsion$,0)$;

$\}$

return Double.compare$($this$.$Prices, o$.$Prices$)$;

$\}$

$//$ testing for compareto

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

$//$ instantiated some resturant item for comparison

ResturantItem R$1=$ new ResturantItem$("$Pizza$",12)$;

ResturantItem R$2=$ new ResturantItem$("$Soup$",10)$;

ResturantItem R$3=$ new ResturantItem$("$CheeseCake$",10)$;

$//$ print the result of the menu order

System.out.println$($R$1.$compareTo$($R$2))$; $//-1$

System.out.println$($R$3.$compareTo$($R$1))$; $//-1$

System.out.println$($R$2.$compareTo$($R$3))$; $//1$

$\}$

$\}$

ResturantItemA.java:

public class ResturantItemA extends ResturantItem $\{$

$//$ declare variable that has integer type

private int calories;

$//$ implement three$-$arg constructor

public ResturantItemA$($String Menu, double Prices, int calories$)\{$

super$($Menu$,$ Prices$)$;

this.calories $=$ calories;

$\}$

$//$ implement getter and setter for instance variable

public int getCalories$()\{$

return calories;

$\}$

public void setCalories$($int calories$)\{$

this.calories $=$ calories;

$\}$

$//$ implement toString that return a string represenation of object where

$//$ instance variable are in one line and separated by tab

@Override

public String toString$()\{$

return super.toString$()+"\backslash$t$"+$ calories;

$\}$

@Override

$//$ implement equals method to check equality of the Item A instance variables

public boolean equals$($Object o$)\{$

if $(!$super.equals$($o$))$

return false;

ResturantItemA ItemA $=($ResturantItemA$)$ o;

return calories $==$ ItemA.calories;

$\}$

$\}$