一些初学shell自己写的一些练习题脚本

1斐波拉契数列前10个 
#!/binbash
#
declare A=0
declare B=1
for ((i=1;i<6;i++)); do
    let A+=B
    printf "%-5s" $A
    let B+=A
    printf "%-5s" $B
done
    printf "\n"

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2、添加用户 ，并且询问是否输入密码，并判断密码的复杂度（包括长度和是否在字典里的常用字符）输入密码确认，创建成功提示。

#!/bin/bash
#
declare A=1
read   -p "please input user: " USER
while [ -z $USER ]; do
  read -p "please input user: " USER
done

if [ $USER == "quit" ] ; then
   exit 0
fi
while  id $USER &> /dev/null ; do
    echo "$USER exist"
    read -t 8 -p "again input user: " USER
done
useradd $USER &> /dev/null
read -t 8 -p "do you want create password:(y|n): " CHOICE
case  $CHOICE  in
y|yes|Y|YES)
      read -p "please input your password: " PASSWORD
      until  [ "$(echo $PASSWORD | sed "s/ //g" | wc -L)" -gt 5 ] ; do
         read -p "password short,please again input: " PASSWORD
      done
      while grep "$PASSWORD" /usr/share/dict/words &> /dev/null; do
        read -p "this password is sight words. again input password: " PASSWORD
      done
        read -p "again input password: " PASSWORD2
      until [ $PASSWORD == $PASSWORD2 ]; do
        read -p  "twice password not atypism,please again input: " PASSWORD2
      done
        echo $PASSWORD | passwd --stdin $USER &> /dev/null
        echo "$USER create finished"

;;
n|N|no|NO)
         echo "$USER Create success,but not set password"
         exit 10
还存在写问题，要进一步修改下

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3、小行星 ，形如

*

***

*****

*******

*********  
#!/bin/bash
#
 for I in `seq 1 2 9`; do
    for ((M=0;M<=$[(9-$I)/2];M++));do
       echo -n " "
    done
    for ((J=0;J<I;J++)); do
       echo -n "*"
    done
    for ((K=0;K<=$[9-$J];K++)); do
       echo -n " "
    done
    for ((M=0;M<=$[(9-$I)/2];M++));do
       echo -n " "
    done
    echo -e "\n"
  done

=======================================================================================================================

模拟系统登陆

#!/bin/bash
#
 user1(){
         while [ -z $USER ];do
           echo -e "\nRed Had Enterprise Linux server 5.8 \nkernel 2.6.18-308.e15 on an x86_64\n"
           read -p "`hostname | awk -F. '{print $1}'`login: " USER
         done
        }
 user2(){
        while [ -z $USER ]; do
        read -p "longin: " USER
        done
        }
passwd1(){
      if [  -z $PASSWORD ]; then
        echo "Login incorrect"  
        exit 10
    fi
        }
login(){
     if  grep "$USER" /root/practice/user &>/dev/null  &&  grep "$PASSWORD" /root/practice/passwd &>/dev/null ; then
       echo -e "\nlast longin: `date` from `ifconfig eth0 | awk -F: '/inet addr/{print $2}' | sed 's/Bcast//g'`"
       exit 0
      fi
}
read -p "`hostname | awk -F. '{print $1}'`login: " USER
user1
read -t  20 -s  -p "passwd: " PASSWORD
passwd1
login
user2
==================================================================================================

5，数字游戏

0

101

21012

3210123

432101234

54321012345

6543210123456

765432101234567

87654321012345678

#!/bin/bash
#
declare A=0
for ((I=1;I<=9;I++)); do
     printf "$A\n\n"
     A=$I$A$I
done

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6，输出乘法口诀表

1x1=1     
1x2=2     2x2=4     
1x3=3     2x3=6     3x3=9     
1x4=4     2x4=8     3x4=12    4x4=16    
1x5=5     2x5=10    3x5=15    4x5=20    5x5=25    
1x6=6     2x6=12    3x6=18    4x6=24    5x6=30    6x6=36    
1x7=7     2x7=14    3x7=21    4x7=28    5x7=35    6x7=42    7x7=49    
1x8=8     2x8=16    3x8=24    4x8=32    5x8=40    6x8=48    7x8=56    8x8=64    
1x9=9     2x9=18    3x9=27    4x9=36    5x9=45    6x9=54    7x9=63    8x9=72    9x9=81

#!/bin/bash
#
for ((i=1;i<10;i++)); do
  for((j=1;j<($i+1);j++)); do
  printf "%-10s" "$j""x""$i""=""$[$j*$i]"
  done
  printf "\n"
done
=====================================================================================================
7，随便给一组数字从大到小排序

#!/bin/bash
#
declare j=0
declare C=0
for I in $*;do
  a[j]=$I
  let j++
 done
 for ((A=0;A<$#;A++));do
      for ((K=$[$A+1];K<$#;K++)); do
        if [ ${a[$K]} -gt ${a[$A]} ]; then
           C=${a[$K]}
           a[$K]=${a[$A]}
           a[$A]=$C
         fi
      done
 done
 echo ${a[*]}

另一个  显示从大到小 ，从小到大

#!/bin/bash
declare i=0
for I in $*; do
 a[i]=$I
 let i++
done
for ((i=0;i<${#a[*]};i++));do
   for ((j=$[$i+1];j<${#a[*]};j++));do
     if [ ${a[j]} -gt ${a[i]} ]; then
        C=${a[j]}
        a[j]=${a[i]}
        a[i]=$C
     fi
    done
done
echo "max to smaill: ${a[*]}"
echo -n "smaill to max: "
for ((i=$#;i>=0;i--)); do
   printf "%s "  "${a[i]}"
done
printf "\n"
~                                                                                                                           
~

==========================================================================================

8，10个随机数  找找出最大数和最小数

#!/bin/bash
#
declare -i A=0
for I in {1..10};do
  declare -i  NUMBER=`echo $RANDOM`
  [ $I -eq 1 ] &&  declare -i  SMAILL=`echo $RANDOM`
  if [ $I -le 9 ]; then
    echo -n "$NUMBER,"
  else
    echo   $NUMBER
  fi
  [ $NUMBER -lt $SMAILL ] && SMAILL=$NUMBER
  [ $NUMBER -gt $A ] && A=$NUMBER
done
  echo "max number is $A"
  echo "smaill number is $SMAILL"
~ ==================================================================================================

10，查看硬盘和内存使用率，可以选择显示什么如下

[root@bogon ok]# sh diskusage.sh
m|M)  show memory utilication.
s|S)  show swap utilication.
d|D)  show disk utilication.
q|Q)  quit..
please choice:

#!/bin/bash
#
LIST(){
cat << EOF
m|M)  show memory utilication.
s|S)  show swap utilication.
d|D)  show disk utilication.
q|Q)  quit..
EOF
}
LIST
read -p "please choice: " OPTION
until [  $OPTION == "Q" -o $OPTION == "q" ] ; do
    case $OPTION in
    m|M)
     free -m | grep "Mem";;
    s|S)
     free -m | grep "Swap";;
    d|D)
     df -lh ;;
    *)
     LIST
     read -p "option error .please again choice: " OPTION
     continue
    ;;
    esac
     LIST
     read -p "please again choice" OPTION
done
~

=======================================================================================

还有好多，慢慢写上来。待续。。。。。

输入用户，判断是否输入为空，输入Q|q 则退出，判断用户是否存在，不存在继续输入，存在则给出选择列表，显示相应的选择，然后让后继续输入，直到输入Q|q

#!/bin/bash
#
read -p "please input user: " USER
while [ -z $USER ]; do
   read -p "please input user: " USER
done
[ $USER == 'q' -o $USER == 'Q' ] && exit 0

until  id $USER &>/dev/null ; do
  read -p "$USER not exist again input: " USER
[ $USER == 'q' -o $USER == 'Q' ] && exit 0
done
cat <<  EOF
#!/bin/bash
#
read -p "please input user: " USER
while [ -z $USER ]; do
   read -p "please input user: " USER
done
[ $USER == 'q' -o $USER == 'Q' ] && exit 0

until  id $USER &>/dev/null ; do
  read -p "$USER not exist again input: " USER
[ $USER == 'q' -o $USER == 'Q' ] && exit 0
done
cat <<  EOF
U|u show UID
G|g show GID
S|s show SHELL
Q|q quit
EOF
read -p "your choice: " CHOICE
while [ -z $CHOICE ] ; do
   read -p "your choice: " CHOICE
done

until [ $CHOICE == "q" -o $CHOICE == "Q" ] ; do
case $CHOICE in
u|U)
   echo "$USER UID is `id -u $USER`"
   read -p "your choice: " CHOICE
   ;;
G|g)
   echo "$USER GID is `id -g $USER`"
   read -p "your choice: " CHOICE
   ;;
S|s)
   echo "$USER SHELL is `grep "$USER\>" /etc/passwd  | awk -F: '{print $NF}'`"
   read -p "your choice: " CHOICE
   ;;
*)
   read -p "choice error  please again your choice: " CHOICE
   ;;
esac
done