酷家乐

• box-sizing

let a = {
  b: 3,
};
function fn(obj) {
  obj.b = 4;
  return obj;
}
let aa = fn(a);
console.log(a.b);
console.log(aa.b);
aa = { b: 6 };
console.log(a.b);
console.log(aa.b);
let len = 6;
for (var i = 0; i < len; i++) {
  setTimeout(() => {
    console.log(i);
  }, 1000);
}
console.log(i);

function Ofo() {}

function Bick() {
  this.name = "mybick";
}

var myBick = new Ofo();

Ofo.prototype = new Bick();

var youbick = new Bick();

console.log(myBick.name);

console.log(youbick.name);

console.log(Ofo.prototype === youbick);