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HomeBackend DevelopmentPHP Tutorial怎么用PHP产生n个数,并让其和为定值

如何用PHP产生n个数,并让其和为定值?
请问各位大侠,如何产生n个数,并使其和为定值?

想实现的功能是:
比如说,有10个站点,随机分配给每个一个百分比,并使和为100%,因为想从若干中方法里选择最好的分配方案,肯定会涉及循环,所以有点糊涂了,还望各位大侠指点迷津,先谢了。

------解决方案--------------------
百度: 整数划分.
------解决方案--------------------
1-100之间,产生n-1个随机数,n+1个数排序,相邻之间的差,就是百分比
------解决方案--------------------
php代码

/**
 +---------------------------------
 * 功能:随机生成10个百分数,其和为1
 * @auathor beatyou385981202
 * @time 2012-6-15
 +---------------------------------
 */

print_r(percentage_num());

function percentage_num()
{
//随机生成的百分数存放位置
$arr_num = array();

//初始化第一个值的范围
$num = 100;

for($i=1;$i {
$arr_num[$i] = random_num($num);
$num = $num - $arr_num[$i];
}

//最后一个百分数,用100减去前5个和
for($i=1;$i {
$add_num += $arr_num[$i];
}

$arr_num[10] = 100 - $add_num;

return $arr_num;
}

function random_num($num)
{
return rand(1,$num/2.5);
//这里将其随机生成的范围缩小,是为了得到结果更加理想
}


希望对lz有用 哈哈
------解决方案--------------------
这不是简单的php随机产生数字问题 这涉及到递归搜索算法

本人是从C语言和数据结构与算法论坛过来的 对算法略懂一二

来分析一下楼主的问题 首先楼主没有给我们解释清楚你的最优到底是什么

但是楼主的最优肯定在我下面状态空间里面 我们可以把这一百个数想象成

一个一百个认得队列,那么第一个人和第一百个人之见肯定会有99个空隙,

其实我们至于把9个隔板任意的放到这99个空隙里面,也就得到了你所要的结果

那么99个空选9个有多少种方法? C(99,9)这个数字是很大的,我们可以计算出来

但是如果要打印出所有的结果恐怕需要很多时间。
------解决方案--------------------

他要0.01做步长.....


探讨

这不是简单的php随机产生数字问题 这涉及到递归搜索算法

本人是从C语言和数据结构与算法论坛过来的 对算法略懂一二

来分析一下楼主的问题 首先楼主没有给我们解释清楚你的最优到底是什么

但是楼主的最优肯定在我下面状态空间里面 我们可以把这一百个数想象成

一个一百个认得队列,那么第一个人和第一百个人之见肯定会有99个空隙,

其实我们至于把9个隔板任意的放到这99……
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