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Java Java Basics Perfecting the Prototype Using Logical ORs and ANDs

KEVIN SINGH
KEVIN SINGH
682 Points
Posted by KEVIN SINGH
KEVIN SINGH
682 Points

explanation of the question

Assuming that Sara has taken the Java and Python tracks, what is the value of isFamiliar below:

boolean isFamiliar = ( learnedJava || learnedPython || learnedRuby );

is said false and it was wrong answer why??

1 Answer

andren
andren
28,558 Points
andren
andren
28,558 Points

Because the OR (||) operator will return true if any of the supplied conditions are true, since learnedPython and learnedJava are true it returns true. It would have returned true even if only one of those were true, it will only return false if all conditions are false.

You can basically read the condition in your example as:

Is learnedJava true? OR is learnedPython true? OR is learnedRuby true? If the answer to any of those questions is yes then it will immediately return true.

The AND (&&) operator works the opposite way, it will only return true if all conditions are true, and false if any single condition is false.

KEVIN SINGH
KEVIN SINGH
682 Points
KEVIN SINGH
KEVIN SINGH
682 Points

thank you very much