<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[]]></title><description><![CDATA[]]></description><link>https://blog.youkuaiyun.com/aoyong9901</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; aoyong9901]]></copyright><item><title><![CDATA[证明 n 等于它所有的因子的欧拉函数之和]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598407</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598407</guid><author>aoyong9901</author><pubDate>Wed, 28 Oct 2015 18:17:00 +0800</pubDate><description><![CDATA[当 n 是质数时，易证。
当 n 是合数时，可以把 n 分解 n=,紧接着求 n 的因子，就是从 n 分解后的东西中选质因子和质因子的幂数，
当 m&gt;1 时，那么可得，因为都小于n，所以可以用归纳法，证明成立。
当 m=1 时，也易证。

另一种证明方法是来自《信息安全数学基础》（陈恭亮）。


转载于:https://www.cnblogs.com/ahahah...]]></description><category></category></item><item><title><![CDATA[hdu5497]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598408</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598408</guid><author>aoyong9901</author><pubDate>Sun, 25 Oct 2015 17:03:00 +0800</pubDate><description><![CDATA[Inversion
Time Limit: 6000/3000 MS(Java/Others)Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 769Accepted Submission(s): 215



Problem Description
You have a s...]]></description><category></category></item><item><title><![CDATA[hdu5496]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598406</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598406</guid><author>aoyong9901</author><pubDate>Sat, 24 Oct 2015 20:36:00 +0800</pubDate><description><![CDATA[Beauty of Sequence
Time Limit: 6000/3000 MS (Java/Others)Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 668Accepted Submission(s): 297



Problem Description
...]]></description><category></category></item><item><title><![CDATA[hdu5495]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598405</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598405</guid><author>aoyong9901</author><pubDate>Sat, 24 Oct 2015 19:16:00 +0800</pubDate><description><![CDATA[LCS
Time Limit: 6000/3000 MS (Java/Others)Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 638Accepted Submission(s): 352



Problem Description

You are given...]]></description><category></category></item><item><title><![CDATA[hdu5501]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598404</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598404</guid><author>aoyong9901</author><pubDate>Sat, 24 Oct 2015 14:37:00 +0800</pubDate><description><![CDATA[参考链接：
官方题解。
对于一个序列，可以先看相邻的两个数，在什么情况下可以交换，使得最后整个序列达到某种最佳状态，那么整个序列就是以什么为标准排序的，比如所这道题中，相邻两个数 bi/ci&lt;bi+1/ci+1 那么就可以交换，所以最后的排序标准是 bi/ci 从大到小排。
关于背包，对应的是选择问题，什么时候选择，什么时候不选择，选择的话选择多少，但是这都是对应的无...]]></description><category></category></item><item><title><![CDATA[hdu5500]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598403</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598403</guid><author>aoyong9901</author><pubDate>Fri, 23 Oct 2015 21:46:00 +0800</pubDate><description><![CDATA[参考链接：官方题解
这道题，不知道为什么，凭直觉写出来后ac，（好神奇）后来看题解才明白证明：首先每个数如果挪的话最多挪一次，其次必须先挪大的再挪小的，最后如果一个数上面有比它的的数，则它一定要挪，否则，不必挪。所以找书的每种放置状态下，需要挪的最大的那个编号的数就可以了。
已ac的代码：
#include&lt;stdio.h&gt;
#include&lt;string...]]></description><category></category></item><item><title><![CDATA[hdu5506]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598402</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598402</guid><author>aoyong9901</author><pubDate>Thu, 22 Oct 2015 20:27:00 +0800</pubDate><description><![CDATA[GT and set

Accepts: 35

Submissions: 194

Time Limit: 2000/1000 MS (Java/Others)

Memory Limit: 65536/65536 K (Java/Others)



问题描述
有NN个集合，每个集合中有A_iA​i​​个数。
你要将这N...]]></description><category></category></item><item><title><![CDATA[hdu5505]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598401</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598401</guid><author>aoyong9901</author><pubDate>Thu, 22 Oct 2015 19:36:00 +0800</pubDate><description><![CDATA[GT and numbers
Time Limit: 2000/1000 MS (Java/Others)Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 1003Accepted Submission(s): 263



Problem Description

Y...]]></description><category></category></item><item><title><![CDATA[hdu5504]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598400</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598400</guid><author>aoyong9901</author><pubDate>Wed, 21 Oct 2015 19:55:00 +0800</pubDate><description><![CDATA[GT and sequence
Time Limit: 2000/1000 MS (Java/Others)Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 1321Accepted Submission(s): 308


Problem Description
You ar...]]></description><category></category></item><item><title><![CDATA[bzoj2186]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598398</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598398</guid><author>aoyong9901</author><pubDate>Tue, 13 Oct 2015 19:13:00 +0800</pubDate><description><![CDATA[2015.10.25
(今天中午本来想定外卖来着，结果昨天晚上吃的那家死活找不到了，于是就饿了肚子。）
t了的思路：
线性求出1到x！之间与x！互质的数的个数：
比如说已经求出了1到 (x-1)!之间与 (x-1)!互质的数的个数n，那么如果x是质数的话，就直接n(x-1),如果x不是质数的话，就直接nx。
比方说当去除掉1到N!之间的x的倍数时，有可能把前面已经剔除掉...]]></description><category></category></item><item><title><![CDATA[判断素数的个数的小程序]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598397</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598397</guid><author>aoyong9901</author><pubDate>Mon, 12 Oct 2015 20:06:00 +0800</pubDate><description><![CDATA[输入n，判断不超过x的素数的个数最大是多少，所以有可能出现输入20，输出27点多。
#include&lt;stdio.h&gt;
#include&lt;string.h&gt;
#include&lt;math.h&gt;
#include&lt;iostream&gt;
using namespace std;
#define e 2.718281828459

int ...]]></description><category></category></item><item><title><![CDATA[f(x)%(p^a)  (p是素数) 求解]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598396</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598396</guid><author>aoyong9901</author><pubDate>Mon, 12 Oct 2015 19:44:00 +0800</pubDate><description><![CDATA[《信息安全数学基础》 陈恭亮
第三章练习题第20题，懒，然后写了个程序，f(x)=x^4+7x+4
2015.10.26
哈哈哈

#include&lt;stdio.h&gt;
#include&lt;string.h&gt;
#include&lt;iostream&gt;
using namespace std;

long long int pro(long l...]]></description><category></category></item><item><title><![CDATA[bzoj3209]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598395</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598395</guid><author>aoyong9901</author><pubDate>Fri, 09 Oct 2015 20:27:00 +0800</pubDate><description><![CDATA[参考链接：
http://blog.youkuaiyun.com/popoqqq/article/details/39936291
感觉数位dp什么的，只要把它分解成一个个的函数，就可以有比较清楚的思路。注意一下细节就可以了。
（省赛时，遇到过数位dp，那时候还不知道是这么个东西，但是凭着直觉，就硬写了下来，写的思路一团糟，但是幸亏ac了，后来知道这是数位dp！）
（意外？不，在加图...]]></description><category></category></item><item><title><![CDATA[bzoj2005]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598394</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598394</guid><author>aoyong9901</author><pubDate>Fri, 09 Oct 2015 19:37:00 +0800</pubDate><description><![CDATA[参考代码：
http://blog.youkuaiyun.com/popoqqq/article/details/39924877
http://blog.youkuaiyun.com/z690933166/article/details/11844077



这道题首先要推出每个点 (i,j) 所消耗的能量就是 (gcd(i,j)-1)*2+1，所以可以把所有最大公约数相同的合并起来，那...]]></description><category></category></item><item><title><![CDATA[bzoj1041]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598393</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598393</guid><author>aoyong9901</author><pubDate>Tue, 06 Oct 2015 20:33:00 +0800</pubDate><description><![CDATA[参考链接： 
http://www.cppblog.com/zxb/archive/2010/10/18/130330.html 
http://blog.youkuaiyun.com/popoqqq/article/details/39895149

《初等数学》（潘承洞）： 
对于具有 
x2+y2=z2 
这种形式的式子来说，求它的本原解 
（即 x&gt;0,y&gt;0...]]></description><category></category></item><item><title><![CDATA[bzoj2142]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598392</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598392</guid><author>aoyong9901</author><pubDate>Mon, 05 Oct 2015 19:48:00 +0800</pubDate><description><![CDATA[参考链接：
http://blog.youkuaiyun.com/popoqqq/article/details/39891263
http://blog.youkuaiyun.com/yerongsc/article/details/8768957

需要转化一下：


ans=C(n,w1)*C(n-w1,w2)*C(n-w1-w2,w3)*...*C(n-w1-w2-...-w_(m...]]></description><category></category></item><item><title><![CDATA[bzoj3629]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598389</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598389</guid><author>aoyong9901</author><pubDate>Mon, 05 Oct 2015 16:14:00 +0800</pubDate><description><![CDATA[参考链接：
http://baike.baidu.com/view/9970469.htm

http://blog.youkuaiyun.com/popoqqq/article/details/39152381

http://blog.youkuaiyun.com/eolv99/article/details/39644419

约数和定理：
对于一个大于1正整数n可以分解质因数：n...]]></description><category></category></item><item><title><![CDATA[bzoj2705]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598388</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598388</guid><author>aoyong9901</author><pubDate>Mon, 05 Oct 2015 09:28:00 +0800</pubDate><description><![CDATA[参考：http://blog.youkuaiyun.com/popoqqq/article/details/39119649
就是求欧拉函数，注意求1的欧拉函数时，这个题中需要时1，即(1,1)互素。

#include&lt;stdio.h&gt;
#include&lt;string.h&gt;
#include&lt;iostream&gt;
using namespace...]]></description><category></category></item><item><title><![CDATA[bzoj2818]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598387</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598387</guid><author>aoyong9901</author><pubDate>Sun, 04 Oct 2015 20:56:00 +0800</pubDate><description><![CDATA[线性筛+线性欧拉函数。
参考：http://blog.youkuaiyun.com/popoqqq/article/details/38760601
（废柴也是木头!只要能烧! ——江南 《龙族·火之晨曦》）

//好搜百科：互质（relatively prime）又叫互素。若N个整数的最大公因数是1，则称这N个整数互质。
#include&lt;stdio.h&gt;
#incl...]]></description><category></category></item><item><title><![CDATA[线性筛]]></title><link>https://blog.youkuaiyun.com/aoyong9901/article/details/101598386</link><guid>https://blog.youkuaiyun.com/aoyong9901/article/details/101598386</guid><author>aoyong9901</author><pubDate>Sun, 04 Oct 2015 20:07:00 +0800</pubDate><description><![CDATA[参考：
http://www.cnblogs.com/zhuohan123/p/3233011.html



  我们现在要求1到N之间的素数。
  我们先尝试把1到N之间的合数分解成a=bp的形式，b是a的最小素因数，那么p的最小素因数一定是大于等于b的，同时p的范围是2到N，每一个1到N的合数的p都在这个范围之间，我们只要遍历p，并且为每个p找到所有合适...]]></description><category></category></item></channel></rss>