[原创]javascript、ruby和C性能一瞥(1)-编程技术-看雪-安全社区|安全招聘|kanxue.com

[原创]javascript、ruby和C性能一瞥(1)

发表于: 2015-4-16 18:19 13776

[原创]javascript、ruby和C性能一瞥(1)

hopy

2015-4-16 18:19

13776

测试一下本地js、浏览器中的js以及ruby对于类似算法的性能。结果有些意外：浏览器js最快，本地其次当相差很小；ruby最慢而且不是一个数量级的；
因为写的匆忙，可能有重大问题没能看出来，请各位高人不吝赐教。
程序计算小于给定数n的最大素数，代码均未作优化，我们依次来看：
首先是浏览器的：

<!DOCTYPE html>
<html>
<head>
    <title>sieve suanfa</title>
    <script src="sieve.js" type="text/javascript"></script>
    <script type="text/javascript">
        window.onload = function(){
            btn_n.onclick = function(){
                var i = parseInt(n.value);
                if(isNaN(i))
                    result.innerHTML = "must input a number";
                else if(i <= 0)
                    result.innerHTML = "must input + number";
                else{
                    var start = new Date().getTime();
                    var max_p = sieve(i);
                    var spend = new Date().getTime() - start;
                    result.innerHTML = "max_p is : " + max_p + "(take " + spend + "ms)";
                }
            }
        }
    </script>
    <style type="text/css">
        #result{
            color: red;
            font-weight: bold;
        }
    </style>
</head>
<body>
<h1>Sieve Suanfa</h1>
<label for="n">input n : </label>
<input type="text" id="n" />
<input type="button" id="btn_n" value="ret max p" />
<label id="result"></label>
</body>
</html>