And
From Free Pascal wiki
Revision as of 05:48, 14 June 2016 by FPC user (talk | contribs) (→Boolean operation: Clarify operands must be Boolean)
│
Deutsch (de) │
English (en) │
español (es) │
suomi (fi) │
français (fr) │
русский (ru) │
Boolean operation
And produces a value of true if and only if both of its Boolean operands are true.
Truth table
| A | B | A and B |
|---|---|---|
| false | false | false |
| false | true | false |
| true | false | false |
| true | true | true |
Bitwise operation
Logical And (aka Bitwise And) requires ordinal operands and sets a bit in the result variable to 1 if and only if both of the corresponding bits in the operands are 1.
Is power of two
function IsPowerOfTwo( const aValue : longint ): boolean;
var
x : longint;
b : boolean;
begin
b := false;
if aValue <> 0 then
begin
x := aValue - 1;
x := x and aValue;
if x = 0 then b := true;
end;
result := b;
end;If you call IsPowerOfTwo(4) then you get true. If you call IsPowerOfTwo(5) then you get false .
