标签：算术运算符脚本
25、编写脚本：传递一个字符串给脚本，脚本会将该字符串当作用户名，如果该用户不存在，则添加之并为其设置与用户名相同的密码
答：
#!/bin/bash
#
if id $1 &> /dev/null; then
echo "$1 is exist."
else
useradd $1
echo "$1" | passwd --stdin $1 &> /dev/null
echo "create $1 successfully"
fi
[root@little ~]# vi w25.sh
[root@little ~]#
[root@little ~]# chmod +x w25.sh
[root@little ~]#
[root@little ~]# ./w25.sh little
little is exist.
[root@little ~]#
26、编写脚本：将两个文本文件的路径传递给脚本作为其参数，如果有文件不存在，则结束脚本执行并报告错误信息；如果文件都存在，则比较两个文件中哪个文件的行数多，返回行数多的文件的文件名。
答：
#!/bin/bash
#
if ! id "$1 && $2" &> /dev/null; then
echo "Error, the parameter is not exist."
exit
fi
line1=$(cat $1 | wc -l)
line2=$(cat $2 | wc -l)
if [ $line1 -gt $line2 ]; then
echo "$1"
else
echo "$2"
fi
[root@little ~]# vi w26.sh
[root@little ~]#
[root@little ~]# chmod +x w26.sh
[root@little ~]#
[root@little ~]# ls
2.txt ace bcf cd6 t1file.txt ??????
24p1.sh acf bcg cdrom w25.sh ??????
24p2.sh acg bde dest w26.sh ??????
24p3.sh ade bdf install.log zhengshu ??????
3.txt adf bdg install.log.syslog ??????
789 adg boot.iso k 67 ?????????
8yu anaconda-ks.cfg c1 my ks.cfg ??????
a123 bce c78m m.z ??????
[root@little ~]#
[root@little ~]# ./w26.sh 2.txt 3.txt
Error, the parameter is not exist.
[root@little ~]# ./w26.sh 24p1.sh 24p2.sh
Error, the parameter is not exist.
27、编写脚本：给脚本传递一个路径作为参数，如果该文件存在，判断其文件类型。
答：
#!/bin/bash
#
if [ -a $1 ]; then
type1=$(file $1)
echo "$type1"
else
echo "$1 is not exist."
fi
[root@little ~]# vi w27.sh
[root@little ~]#
[root@little ~]# chmod +x w27.sh
[root@little ~]#
[root@little ~]# ./w27.sh w26.sh
file w26.sh
[root@little ~]# ./w27.sh 3.txt
file 3.txt
[root@little ~]# vi w27.sh
[root@little ~]#
[root@little ~]# ./w27.sh 3.txt
3.txt: ASCII text
[root@little ~]#
28、编写脚本：给脚本传递三个整数，要求：
1) 如果用户传递过来的不是三个参数，报告正确用法；
2) 如果三个参数中有非纯数字字符串，报告错误并提示用户输入数字；
3) 从三个整数中的选出最大数和最小数，并显示出来；
答：
#!/bin/bash
#
if [ $# -ne 3 ]; then
echo "Usage: $(basename $0) integer1 integer2 integer3"
exit
fi
if echo "$1 $2 $3" | grep "\<[^[:digit:]]\+\>" &> /dev/null; then
echo "please input 3 integers."
exit
fi
if [ $1 -gt $2 ]; then
if [ $1 -gt $3 ]; then
echo "max is $1"
if [ $2 -gt $3 ]; then
echo "min is $3"
else
echo "min is $2"
fi
else
echo "max is $3"
echo "min is $2"
fi
exit
fi
if [ $2 -gt $1 ]; then
if [ $2 -gt $3 ]; then
echo "max is $2"
if [ $1 -gt $3 ]; then
echo "min is $3"
else
echo "min is $1"
fi
else
echo "max is $3"
echo "min is $1"
fi
exit
fi
if [ $3 -gt $2 ]; then
if [ $3 -gt $1 ]; then
echo "max is $3"
if [ $2 -gt $1 ]; then
echo "min is $1"
else
echo "min is $2"
fi
else
echo "max is $1"
echo "min is $2"
fi
exit
fi
[root@little ~]# vi w28.sh
[root@little ~]# chmod +x w28.sh
[root@little ~]#
[root@little ~]# ./w28.sh
Usage: w28.sh integer1 integer2 integer3
[root@little ~]#
[root@little ~]# ./w28.sh 12 q 23
please input 3 integers.
[root@little ~]#
[root@little ~]# ./w28.sh 12 13 14
max is 14
min is 12
max is 14
min is 12
[root@little ~]# vi w28.sh
[root@little ~]#
[root@little ~]# ./w28.sh 12 13 14
max is 14
min is 12
[root@little ~]#
29、传递三个参数给脚本，第一个为整数，第二个为算术运算符(包括基本的加、减、乘、除、取模运算符即可)，第三个为整数，将计算结果显示出来；要求：
1) 判断第一个和第三个参数是否为整数；
2) 判断第二个算术运算符必须是给定的运算符中的一个，否则报错；
3) 如果是除法，在不能整除的情况下，保留两位精度。
答：
#!/bin/bash
#
if [ $# -ne 3 ]; then
echo "please input 3 parameter"
exit
fi
if echo $1 | grep "^\<[[:digit:]]\+\>$" &> /dev/null; then
if echo $3 | grep "^\<[[:digit:]]\+\>$" &> /dev/null; then
if echo $2 | grep "+\|-\|*\|%" &> /dev/null; then
let result=$[$1$2$3]
echo "$result"
elif echo $2 | grep "\/" &> /dev/null; then
echo "scale=2;$1/$3" | bc
else
echo "$2 is error"
fi
fi
fi
[root@little ~]# vi w29.sh
[root@little ~]# chmod +x w29.sh
[root@little ~]#
[root@little ~]# ./w29.sh
[root@little ~]#
[root@little ~]# echo $?
0
[root@little ~]# ./w29.sh 2 - 1
1
[root@little ~]# ./w29.sh 2 / 1
2.00
[root@little ~]# ./w29.sh 10 / 5
2.00
[root@little ~]# vi w29.sh
[root@little ~]#
[root@little ~]# ./w29.sh
./w29.sh: line 3: syntax error near unexpected token `fi‘
./w29.sh: line 3: `fi [ $# -ne 3 ]; then‘
[root@little ~]# vi +3 w29.sh
[root@little ~]#
[root@little ~]# ./w29.sh
please input 3 parameter
[root@little ~]#
30、求100以内所有偶数之和以及奇数之和。
答：
#!/bin/bash
#
sum1=0
sum2=0
for i in $(seq 1 2 100); do
sum1=$[$sum1+$i]
done
echo "simple sum is $sum1"
for j in $(seq 2 2 100); do
sum2=$[$sum2+$j]
done
echo "double sum is $sum2"
[root@little ~]# vi w30.sh
[root@little ~]# chmod +x w30.sh
[root@little ~]#
[root@little ~]# ./w30.sh
simple sum is 2500
double sum is 2550
[root@little ~]#
标签：算术运算符脚本
原文地址：http://12496428.blog.51cto.com/12486428/1984026
