Exchange the value of two variables, without the help of the third variable three methods (JS implementation)

The first type: arithmetic Operation method

Its principle is: The A, b as a point on the axis, around the distance between two points to calculate.
The specific process: the first sentence "a=b-a" to find the distance ab two points, and save it in a, the second sentence "b=b-a" to find a to the origin of the distance (b to the origin of the distance and the difference between AB two points), and save it in B; the third sentence "A=b+a" Find the distance from the B to the origin (the sum of the distance from a to the origin of the AB two point) and save it in a. Complete the interchange.

Effect:

The second type: with an array

The principle does not need to say much, with the help of array subscript and operator priority implementation

var a = 1,b = 2;a = [B, b = a][0];

Effect:

The third type: bitwise arithmetic

Principle:

The ^ operator is similar to |, but a little different is that if two operation bits are 1, the result is 0.

1 binary representation is 0 0 0 0 0 0 1

3 binary representation is 0 0 0 0 0 1 1

So the result of 1 ^ 3 is 2

Effect:

Exchange the value of two variables, without the help of the third variable three methods (JS implementation)