how many does the factorial of n（in binary data ） have zero?

how many does the factorial of n（in binary data ） have zero?

个人信息：就读于燕大本科软件工程专业 目前大三;

本人博客：google搜索“cqs_2012”即可;

个人爱好：酷爱数据结构和算法，希望将来从事算法工作为人民作出自己的贡献;

博客内容：how many does the factorial of n have zero?

博客时间：2014-5-6;

编程语言：Java ;

编程坏境：Windows 7 专业版 x64;

编程工具：jdk，eclipse x64;

制图工具：office 2010 ppt;

硬件信息：7G-3 笔记本;

my words

Attitude beats all.

problem( from beauty of programming )

how many does the factorial of n（in binary data ） have zero?

eg: n = 5;

n! = 1 * 2 * 3 * 4 * 5  =  120 =  0111 1000 ;

the right result is 3.

my solution 

as for n!, the time that n! can divided by 2 without reminder is the result.

experiments

program note:

for every row 

first number: n

second number: the result the problem require

my code

test.java

package test;


public class test {

	public static void main(String[] args) {
		int i =0;
		while(i < 100)
			System.out.println(i+" "+_zero_number_with_binary(i++));

	}

	static int _zero_number_with_binary(int n)
	{
		int result = 0;
		int i = n ;
		while(i>0)
		{
			result += i/2 ;
			i = i/2 ;
		}
		return result;
	}

}