No. In this defective fragment, the NOT (the !) applies directly to cost.
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.
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.