leetcode：Tenth Line 【shell】

一、问题描述

How would you print just the 10th line of a file?

For example, assume that file.txt has the following content:

Line 1
Line 2
Line 3
Line 4
Line 5
Line 6
Line 7
Line 8
Line 9
Line 10

Your script should output the tenth line, which is:
Line 10

二、问题分析

1. shell整形变量操作，参考链接
2. 按行读取文件，参考链接
3. while循环，参考链接
4. if判断，参考链接

三、shell代码

# Read from the file file.txt and output the tenth line to stdout.
declare -i count=0 #声明count为整形变量
cat file.txt | while read line
do
let count++; #使count加1
if [ $count -eq 10 ]; then
echo $line
fi
done