Short Circuit Evaluation

Both && and || use short circuit evaluation. That means that the second condition isn’t necessarily checked if the result from the first condition is enough to tell if the result is true or false. In a complex conditional with a logical and (&&) both conditions must be true, so if the first is false, then the second doesn’t have to be evaluated. If the complex conditional uses a logical or (||) and the first condition is true, then the second condition won’t be executed, since only one of the conditions needs to be true.

Note

In a complex conditional using a logical and (&&) the evaluation will short circuit (not execute the second condition) if the first condition is false. In a complex conditional using a logical or (||) the evaluation will short circuit if the first condition is true.

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