- finite undirected gragh ∑deg(v) = 2|E| In a k-ary tree where every node has either 0 or k children, following property is always true. L = (k - )*I + Where L = Number of leaf nodes I = Number of internal nodes case: root is leaf/internal node Sum o…

[2018HN省队集训D6T2] girls 题意 给定一张 \(n\) 个点 \(m\) 条边的无向图, 求选三个不同结点并使它们两两不邻接的所有方案的权值和 \(\bmod 2^{64}\) 的值. 一个方案 \((i,j,k)\) 的权值定义为 \(iA+jB+kC\), 其中 \(A,B,C\) 给定且 \(i<j<k\). 点从 \(0\) 开始标号. \(n,m\le 2\times 10^5\). 题解 出题人: 用心造题, 用脚造数据 这题场上看出标算, 然而其中 \(2\)…

tomcat访问https请求返回: javax.net.ssl.SSLProtocolException: handshake alert:  unrecognized_name at sun.security.ssl.ClientHandshaker.handshakeAlert(ClientHandshaker.java:1292) at sun.security.ssl.SSLSocketImpl.recvAlert(SSLSocketImpl.java:1952) at sun.sec…

今天将jdk从1.6升级到1.7,但是HttpUrlConnection连接https出现问题了. javax.net.ssl.SSLProtocolException: handshake alert: unrecognized_name at sun.security.ssl.ClientHandshaker.handshakeAlert(ClientHandshaker.java:1288) at sun.security.ssl.SSLSocketImpl.recvAlert(SSLSo…

使用标准的JSR 356注解时,需要使用tomcat 8.x版本,如果使用tomcat 7.x的版本,则需要继承WebSocketServlet,否则会报WebSocket connection to,Error during WebSocket handshake: Unexpected response code: 404.…

文章作者:luxianghao 文章来源:http://www.cnblogs.com/luxianghao/p/6239518.html  转载请注明,谢谢合作. 免责声明:文章内容仅代表个人观点,如有不当,欢迎指正. --- 事情起因 某日,突然之前ok的访问不ok了,具体情况如下 [root@host tmp]# wget https://cdn.example.com/monitor/test.txt    --2016-12-22 12:57:34--  https://cdn.exa…

目的 为能够透彻理解HTTPS报文交互过程,做此笔记. 本文大部分内容来自 : http://albertx.mx/blog/https-handshake/ http://www.cnblogs.com/svan/p/5090201.html TLS Handshake Protocol The TLS Handshake its like a sub-protocol of the TLS protocol. Its purpose is to define the algorithms a…

jdk1.7提示:javax.net.ssl.SSLProtocolException: handshake alert: unrecognized_name //方案1:设置系统属性:System.setProperty("jsse.enableSNIExtension", "false"); //方案2:如果是tomcat: // 1. linux,在catalina.sh加上JAVA_OPTS="$JAVA_OPTS -Djsse.enableSNI…

问题:在WINDOWS中创建的SVN Server,在Linux client中无法连接.原因:WINDOWS中的证书无法被Linux正确识别,因此需要修改证书,以使双方都可以正确识别. 修改方法如下:(在网上搜到的解决办法,特放在这里以备忘.) http://www.visualsvn.com/support/topic/00056/ SymptomsSubversion clients receive the following error message when attempting t…

Subversion clients receive the following error message when attempting to connect to VisualSVN Server: svn: OPTIONS of 'https://server.domain.local/svn/repo': SSL handshake failed: SSL error:Key usage violation in certificate has been detected. (http…