SOURCE

console 命令行工具 X clear

                    
>
console
var str ="Rome was not built in a day";
str =str.replace(/\s/g, "");
var sum =0;
for(var i of str)
{
    sum++;
}
 document.write(sum);
<!DOCTYPE html>
<html>
<head>
    <meta charsrt="utf-8" />
    <title></title>
</head>
<body>
    <script>

    </script>
</body>
</html>