Precedence of NOT

The NOT operator has high precedence, so it is done before arithmetic and relational operators unless you use parentheses. Examine the following:

!cost < 50 
-----  
illegal: can't use ! on an arithmetic variable

Since ! has high precedence, the above says to apply it to cost. This which won't work, because cost is an integer and NOT applies only to boolean values.

QUESTION 24:

Look at this fragment:

if ( cost < 50  )
  System.out.println("Acceptable shoes");
else
  System.out.println("Reject these shoes");

Is the new fragment equivalent to the original fragment:

if (  !(cost < 50)  )
  System.out.println("Reject these shoes");
else
  System.out.println("Acceptable shoes");

Try a few trial costs with each fragment to see if they are equivalent.