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shell打印字符长度

编写shell脚本以打印下面语句中字符数小于6的单词。

The hard part isn’t making the decision. It’s living with it.

思路：首先取出所有单词，计算每个单词的长度，然后依次进行判断

计算变量内容的长度，常见的方法有四种：

1.变量自带的获取长度的方法 echo ${#str}

$ str=abc
$ echo ${#str}
3

2.管道加wc -L方法

$ str=abc

#-L 打印行长度
$ echo $str|wc -L		
3

3.利用expr自带的length方法

$ str=abc
$ expr length $str
3

4.利用awk自带的length函数方法

$ str=abc
$ echo $str|awk '{print length ($0)}'
3

结合for循环截取字符串

结合for循环截取字符串，例如截取给定字符串中长度大于某一个值或小于某一个值

例句：The hard part isn't making the decision. It's living with it.

截取例句中单词长度大于5的单词

方法一 $

#编辑脚本
cat >test.sh<<'EOF'
#!/usr/bin/env bash
#
str="The hard part isn't making the decision. It's living with it"
for i in $str
do
   if [ ${#i} -gt 5 ];then
      echo $i
   fi
done
EOF

#执行脚本
$ sh test.sh
making
decision.
living   

方法二 wc -L

#编辑脚本
cat >test.sh<<'EOF'
#!/usr/bin/env bash
str="The hard part isn't making the decision. It's living with it"

for i in $str
do
   if [ `echo $i|wc -L` -gt 5 ];then
      echo $i
   fi
done
EOF

#执行脚本
$ sh test.sh
making
decision.
living

方法三 利用expr自带的length方法

#编辑脚本
cat >test.sh<<'EOF'
#!/usr/bin/env bash
str="The hard part isn't making the decision. It's living with it"

for i in $str
do
   if [ `expr length $i` -gt 5 ];then
      echo $i
   fi
done
EOF

#执行脚本
$ sh test.sh
making
decision.
living

方法四 利用awk自带的length函数方法

#编辑脚本
cat >test.sh<<'EOF'
#!/usr/bin/env bash
str="The hard part isn't making the decision. It's living with it"

for i in $str
do
   if [ `echo $i|awk '{print length ($0)}'` -gt 5 ];then
      echo $i
   fi
done
EOF

#执行脚本
$ sh test.sh
making
decision.
living