花式交換兩個數(shù)值

方案一

var a = 1, b =2;
a = [b, b = a][0];
console.log(a, b);  //2 1

方案二

var a = 1, b =2;
a = a ^ b;
b = a ^ b;
a = a ^ b;
console.log(a,b)  //2 1

方案三

let a=1,b=2;
[a,b]=[b,a]