linux shell语法综合实践1取出字符超过6个的单词

#!/bin/bash

arr=(      #定义数组  arr =()
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)

len=${#arr[*]}  #取数组长度不是$(#arr[*])
echo $len
for(( i=0; i < len; i++ ))
do                                                     #[]中括号各空一个空格否则报错 testfor.sh: line 10: [1: command not found
    if [ `expr length ${arr[$i]}` -le 6 ]  #[]中是-le非