i need help to find the error

public static void hackSalary(int a) {
    int Salary = a;                         // no need to do this
    int NewSalary= a+1000;          // a = a + 100 can do the work for us instead of creating 2 new variables
    System.out.println("Your salary is:" +(+a+1000)+ "dollars per month.");
    /*
    Instead of (+a+1000) you could have used NewSalary or a+1000
    And also spacing is required after is and behind the dollars.
    */
}

public static void hackSalary(int a) {
    a = a+1000;
    System.out.println("Your salary is: " + a + " dollars per month.");
}

public static void hackSalary(int a) {
        int Salary = a;
        int NewSalary = a+1000;
        System.out.println("Your salary is: "  + NewSalary +  " dollars per month.");
}