JavaScript two-dollar operator && and | | __javascript

On the internet to see a face test, as follows:

Write alert (1&&2), Alert (1| | 0) output results.

alert (1&&2); 2
alert (1| | 0); 1

Output results 2 and 1.

Knowledge Points:

&& operator rule: a&&b, if A is true, returns B directly, or returns a If a is false.

| | operator rule: a | | b, if A is true, return directly A; If A is false, then return B directly.

&& priority is higher than | |

See more examples to enhance memory

Alert ((1 && 3 | | 0) && 4); 4
Alert (1 && 3 | | 0 && 4);//3
alert (0 && 3 | | 1 && 4);//4
alert (1 &&am P 3 | | 1 && 4); 3