Write a PL/SQL block to display the name of the department and their costliest employee

DECLARE
    CURSOR department_cur IS
      SELECT department_id,
             department_name,
             Max(salary) maxsalary
      FROM   employees
             join departments USING (department_id)
      GROUP  BY department_id,
                department_name;
    emp_first_name employees.first_name%TYPE;
BEGIN
dbms_output.Put_line('------------------------------------------------------------');

dbms_output.Put_line(Rpad('Name of the Department', 35)
                     ||Rpad('First Name', 25));

dbms_output.Put_line('------------------------------------------------------------');

FOR emp_dept_cur IN department_cur LOOP
    BEGIN
        SELECT first_name
        INTO   emp_first_name
        FROM   employees
        WHERE  department_id = emp_dept_cur.department_id
               AND salary = emp_dept_cur.maxsalary;

        dbms_output.Put_line(Rpad(emp_dept_cur.department_name, 35)
                             || Rpad(emp_first_name, 25));
    EXCEPTION
        WHEN too_many_rows THEN
          dbms_output.Put_line(Rpad(emp_dept_cur.department_name, 35)
                               || ' - More than one employee');
    END;
END LOOP;
END; 
/