养兔子Fibo函数优化 

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>
    var month =  prompt("请输入月数：")
    function fibobo(x) {
        var arr = [1, 1];
        (function fib(n) {
            if (n === 0 || n === 1) {
                return 1;
            }
            if (!arr[n]) {
                arr.push(fib(n - 1) + fib(n - 2));
                return arr[n];
            } else {
                return arr[n];
            }
        })(x);
        return arr[x - 1];
    }
    console.time('优化后方案')
    console.log(month+"个月后有"+fibobo(month)+"只兔子");
    console.timeEnd('优化后方案')
    function fib(n) {
        if (n<=2){
           return 1 ;
        }
        return fib(n -1 ) + fib(n - 2);
    }
    console.time('优化前方案')
    console.log(month+"个月后有"+fib(month)+"只兔子");
    console.timeEnd('优化前方案');
</script>
</body>
</html>

 

posted @ 2017-02-23 22:37  一混五六年  阅读(308)  评论(0)  编辑  收藏  举报