reverse.sh

#反转字符串

#输入：字符串

#输出：以两个字符为单位，将字符串反转，保存在变量ret

 

reverse()

{

    tmpStr=$1

    tmpLen=${#1}

    tmp=`expr $tmpLen % 2`

    if ( test $tmp != 0 )

    then

        echo Error: length of string:

        echo Error: /"$1/"

        echo Error: $tmpLen

        echo Error: is not a multiple of 2, Please check!

        exit

    fi

 

    ret=""

    tmp=`expr $tmpLen / 2`

    echo Reversing: $tmpStr

    for i in `seq 1 $tmp`

    do

        j=`expr $i /* 2 - 1`

        ret=`expr substr "$tmpStr" $j 2`$ret

    done

    echo --------/>: $ret

    echo [OK]

}