AP CS A Unit 3

Block of Statements

**One or more statements enclosed in an open curly brace** 

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**'{' and a closing curly brace '}'.**

**Boolean expression**

**A mathematical or logical expression that is either true or false.** 

complex conditional

**A Boolean expression with two or more conditions joined** 

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**by a logical and '&&' or a logical or '||'.**

conditional

Used to execute code only if a Boolean expression is true.

DeMorgan's Laws

Rules about how to distribute a negation on a complex conditional.

logical and(&&)

Used to only execute the following statement or block of statements if both conditions are true

logical or( || )

Used to execute the following statement or block of statements if one of the conditions are true

negation( ! )

turns a true statement false and a false statement true

short circuit evaluation

**The type of evaluation used for logical and '&&' and logical or '||' expressions. If the first condition is false in a complex conditional with a logical and the second condition won't be evaluated. If the first condition is true is a complex conditional with a logical or the second condition won't be evaluated.**

if (Boolean expression)

**used to start a conditional statement. This is followed by a statement or a block of statements that will be executed if the Boolean expression is true.**

else

used to execute a statement or block of statements if the Boolean expression on the if part was false.

else if (Boolean expression)

**used to have 3 or more possible outcomes such as if x is equal, x is greater than, or x is less than some value. It will only execute if the condition in the 'if' was false and the condition in the else if is true.**