zoukankan      html  css  js  c++  java
  • 一张图理解shell内核

     1 #!/bin/bash
     2 name="liu de hua";#name后面=不能有空格
     3 echo "hello word ${name}work $name";
     4 name="zhou run fa"; readonly url="http://www.daokr.com";
     5 echo "hello ${name}";
     6 #url="www.baidu.com";#只读变量不能修改
     7 echo "设置的url=${url}";
     8 unset url;#无法删除只读变量
     9 unset name;
    10 echo "删除的url=${url} 删除name=${name}";
    11 #获取name字符串的长度
    12 name="zhong guo";
    13 echo "name:"${name}"的长度length:${#name}";
    14 #把ong从name字符串中提取出来
    15 newname=${name:2:3};
    16 echo "newname:${newname}";
    17 #从字符串name中查找出ng的位置
    18 pos=`expr index "${name}" zh`;
    19 echo ""zh"在"zhong guo"字符串里的位置是:${pos}"
    20 
    21 #shell中使用数组
    22 myarr=(wangli jun zhonguo);
    23 echo ${myarr[0]} 
    24 echo ${myarr[2]}
    25 #设置数组成员
    26 myarr[3]="test work"
    27 echo ${myarr[3]}
    28 #计算myarr的元素个数
    29 echo ${myarr[@]}数组元素个数:${#myarr[*]} 或者 ${#myarr[@]}

     

  • 相关阅读:
    378. Kth Smallest Element in a Sorted Matrix
    372. Super Pow
    357. Count Numbers with Unique Digits
    345. Reverse Vowels of a String
    343. Integer Break
    347. Top K Frequent Elements
    344. Reverse String
    338. Counting Bits
    326. Power of Three
    python练习
  • 原文地址:https://www.cnblogs.com/wanglijun/p/8670554.html
Copyright © 2011-2022 走看看