kaichao

import java.util.Stack;

/**
 * 递归求解汉诺塔
 */
public class HanoiTower {
    // 三个塔 a、b、c
    Stack<Integer> a,b,c;

    public static void main(String[] args) {

kaichao

    String dataFile = "data/NWP_NMC_T639R/Z_NAFP_C_BABJ_20161108000000_P_CNPC-T639-GMFS-HNEHE-00000.grib2";
    try {
        // open netcdf/grib/grib2 file from argument
        NetcdfDataset gid = NetcdfDataset.openDataset(dataFile);
        // get all grid tables in the file
        List<Variable> variables = gid.getReferencedFile().getVariables();
        for (int i = 0; i < variables.size(); i++) {
            Variable var = variables.get(i);
            if ((!var.isMetadata()) && (!var.getRanges().isEmpty())) {
                System.out.format("%s, %s: %s %s\n", var.getName(), var.getDataType().toString(),var.getRanges().toString(),var.getUnitsString());

kaichao

信息学程序模板

#include<iostream>
#include<stdio.h>
using namespace std;
int main(){
    if(freopen("bus.in","r",stdin)==NULL)
        printf("error while opening input file.\n");
    if(freopen("bus.out","w",stdout)==NULL)
 printf("error while opening output file.\n");

kaichao

编辑/etc/default/grub文件：
GRUB_CMDLINE_LINUX参数加上ipv6.disable=1

以root运行命令：
grub2-mkconfig -o /boot/grub2/grub.cfg

编辑/etc/ssh/sshd_config 文件，增加一行：
AddressFamily inet

kaichao

1.升级Linux内核达到4.9以上
2.验证BBR是否已经可用。
  A. 验证当前TCP控制算法的命令：
    sysctl net.ipv4.tcp_available_congestion_control 
  返回值一般为：
     net.ipv4.tcp_available_congestion_control = bbr cubic reno
  或者为：
     net.ipv4.tcp_available_congestion_control = reno cubic bbr
  B. 验证BBR是否已经启动。
     sysctl net.ipv4.tcp_congestion_control 

kaichao

安装CentOS 7.x，升级内核

rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
rpm -Uvh https://www.elrepo.org/elrepo-release-7.0-4.el7.elrepo.noarch.rpm
yum --disablerepo="*" --enablerepo="elrepo-kernel" list available
yum --enablerepo=elrepo-kernel install -y kernel-ml

# 若出错，则运行以下命令
#grub2-mkconfig -o /boot/grub2/grub-efi.cfg
awk -F\' '$1=="menuentry " {print i++ " : " $2}' /etc/grub2.cfg

kaichao

brew的proxy设置

git config --global http.proxy 'socks5://10.255.128.1:1080'
git config --global https.proxy 'socks5://10.255.128.1:1080'

echo 'proxy=socks5://10.255.128.1:1080' >> ~/.curlrc 

CentOS7上的git2

kaichao

1. switch nginx image to openresty/openresty

2. add the following to server/location (/etc/nginx/conf.d/default.conf)

   set $req_header "";
   set $resp_header "";
   header_filter_by_lua_block{ 
      local h = ngx.req.get_headers();
      for k, v in pairs(h) do
         ngx.var.req_header = ngx.var.req_header .. k.."="..v.." ";

kaichao

分布式ping： http://ping.pe/

移动光猫：CMCCAdmin/aDm8H%MdA 改为桥接模式：https://www.sciencesoft.cn/china-mobile-routing-to-bridge-mode/

kaichao

## Cannot git-clone from github

```bash

git clone https://github.com/kaichao/app-mwa.git
Cloning into 'app-mwa'...
fatal: unable to access 'https://github.com/kaichao/app-mwa.git/': GnuTLS recv error (-110): The TLS connection was non-properly terminated.

```