[Linux手撕]

有效的电话号码

grep -E '^(\([0-9]{3}\) [0-9]{3}-[0-9]{4}|[0-9]{3}-[0-9]{3}-[0-9]{4})$' file.txt

打印第十行

awk "NR==10" file.txt

sed -n '10p' file.txt

tail -n +10 file.txt | head -1

Linux 从日志获取ip 取top10

awk '{print $1}' access.log | sort | uniq -c | sort -nr | head -n 10