ssh需要密码？用密钥id_rsa && 递归与迭代（recursive and iterative）

id_rsa

很多时候，比如jenkins的用git拉代码，如果slave或者jenkins主机不安装git的私钥的话，单纯的配置ssh与git路径，ms是行不通的。

git服务器生成id_rsa

ssh-keygen -t rsa -C "ur_email@example.com" ssh-agent -s ssh-add ~/.ssh/id_rsa

将git服务器的id_rsa放到slave或者jenkins主机上

chmod 600 id_rsa

mv id_rsa XXXName

touch ~/.ssh/config

add:

Host git.XXX.com
IdentityFile /home/XXX/.ssh/keys/git_XXX_com
Port 22
User git

然后将命名为XXXName的私钥放到~/.ssh/keys文件中，此config则起到管理不同机器之间的私钥。

jenkins 的slave配置

tools location 添加slave的java git mvn等bin目录

slave机器的$HOME 目录创建.m 目录，然后将setting文件放到里面

递归与迭代 recursive and iterative

递归

int recursive(int n){
    if(n <= 1) return 1;
    return n*recursive(n-1);
}

int iterative(int n){
    int sum = 1;
    if(n <= 1) return sum;
    while(n > 1){
        sum *= n;
        n--;
    }
    return sum;
}



//--------------- iterative version ---------------------    

static int FibonacciIterative(int n)
{
    if (n == 0) return 0;
    if (n == 1) return 1;
        
    int prevPrev = 0;
    int prev = 1;
    int result = 0;
        
    for (int i = 2; i <= n; i++)
    {
        result = prev + prevPrev;
        prevPrev = prev;
        prev = result;
    }
    return result;
}
    
//--------------- naive recursive version --------------------- 

static int FibonacciRecursive(int n)
{
    if (n == 0) return 0;
    if (n == 1) return 1;
        
    return FibonacciRecursive(n - 1) + FibonacciRecursive(n - 2);
}
    
//--------------- optimized recursive version ---------------------

static Dictionary<int> resultHistory = new Dictionary<int>();

static int FibonacciRecursiveOpt(int n)
{
    if (n == 0) return 0;
    if (n == 1) return 1;
    if (resultHistory.ContainsKey(n)) 
        return resultHistory[n];

    int result = FibonacciRecursiveOpt(n - 1) + FibonacciRecursiveOpt(n - 2);
    resultHistory[n] = result;
        
    return result;
}

广度优先与深度优先

Tips

删除Existed的container

docker rm -f $(docker ps -a |grep Exited|awk '{print $1}')

删除的images

docker rmi -f $(docker images |grep '<none>' |awk '{print $3}')