题解 | #打印每一行出现的数字个数#

还没学到grep命令，就直接用-eq判断了;
read循环读取每一行;
然后获得每行的字符串的长度;
然后依次截取其中一个字符;
然后判断是否等于12345;
最后就是累加求和了;

#!/bin/bash
row=0
sum=0
while read line
do
        num=0
        len=${#line}
        for((i=0;i<len;i++))
        do
                tmp=${line:i:1}
                if [[ ${tmp} -eq 1 || ${tmp} -eq 2 || ${tmp} -eq 3 || ${tmp} -eq 4 || ${tmp} -eq 5 ]]
                then
                        ((num++))
                fi
        done
        ((row++))
        ((sum+=num))
        echo "line${row} number:${num}"
done < nowcoder.txt
echo "sum is ${sum}"