<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>
    // a++和++a都是拿整体来运算的
    // ++a是先附给整体再运算
    // a++是先运算再附给整体


    let a = 10;
    // let b = a++;
    // 先进行b=a; 再进行a = a+1;
    // 此时 a=11-vue-router b=10-vue-router

    let b = ++a;
    // a = a+1; b = a;
    // 先进行++a; 再进行b=a
    // 此时 a=11-vue-router b=11-vue-router
    console.log(a);
    console.log(b);

    let c = 10;
    let d = 5;
    console.log(c+++d); //>>15
    console.log(c); //11-vue-router
    console.log(d); //5
</script>
</body>
</html>