简化布尔表达式

Question

Here b is a variable of type boolean:

(a) b == true
(b) b == false
(c) b != true
(d) b != false

i want to Simplify the following expressions.

what i had try so far is

a) if (b)

b)

c) if (!b)

Answer 1

You're on your way

"!= true" = false;

"!= false" = true

(a) b == true
    if (b)
(b) b == false
    if (!b)
(c) b != true
    if (!b)
(d) b != false
    if (b)

EDIT: Three answers, all the same and correct. I don't know why one user downvoted them all. The answerer can't help noob-questions being asked here.

Answer 2

a) if(b)
b) if(!b)
c) if(!b)
d) if(b) (because of double negation, not false is true)

More info about the Java Boolean Condition Logic : http://codingbat.com/doc/java-if-boolean-logic.html

Have a good day ;)

Answer 3

I'm not really sure what you're trying to achieve but with what you have given:

(a) b == true
(b) b == false
(c) b != true
(d) b != false

Then you get:

(a) if(b)    // Because b is true

(b) if(!b)   // Because b is false then the ! (not) operator will give you true.
             // You're basically saying "if b is not true then this statement is true"

(c) if(!b)   // The assignment say here "b is not true" so therefore: b is false.
             // So now you can use the same logic as in (b)

(d) if(b)    // Here the assignment says "b is not false" therefore: b is true.
             // So now you use the same logic as i (a)

Hope this is what you were going for. Next question you ask here should be explained a little more thoroughly :)