Felix Cai

``` var a = { value: 1, toString: function() { return a.value++; }, }; if(a == 1 && a == 2 && a == 3){ console.log(1); } ```

```javascript function rotate(arr, k) { arr.unshift(...arr.splice(arr.length - k, k)); return arr; } ```

``` function mergeArray(a,b) { return a.concat(b).sort((a,b) => { if (a.charCodeAt() === b.charCodeAt()) { return 0 }; return a.charCodeAt() > b.charCodeAt() ? 1 : -1; }); }; mergeArray(['A1', 'A2', 'B1', 'B2',...

``` // 1 使用es5 块级作用域 let for (let i = 0; i< 10; i++){ setTimeout(() => { console.log(i); }, 1000) } // 2 闭包法 for (var i = 0; i<...

```css // 1. line-height + text-algin .parent { height: 100px; line-height: 100px; text-align: center; } .child { } // 2. text-align + vertail-align .parent { text-align: center; } .child {...