[Bash]LeetCode195. 第十行 | Tenth Line

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Given a text file file.txt, print just the 10th line of the file.

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

Note:
1. If the file contains less than 10 lines, what should you output?
2. There's at least three different solutions. Try to explore all possibilities.

---

给定一个文本文件 file.txt，请只打印这个文件中的第十行。

示例:

假设 file.txt 有如下内容：

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

你的脚本应当显示第十行：

Line 10

说明:
1. 如果文件少于十行，你应当输出什么？
2. 至少有三种不同的解法，请尝试尽可能多的方法来解题。

---

 4ms

# Read from the file file.txt and output the tenth line to stdout.
sed -n 10p file.txt

---

4ms

# Read from the file file.txt and output the tenth line to stdout.
awk 'NR==10' file.txt

---

8ms

# Read from the file file.txt and output the tenth line to stdout.
{ cat file.txt; for (( i = 1; i <= 10; ++i)); do echo ; done } | head -n 10 | tail -n 1

---

12ms

# Read from the file file.txt and output the tenth line to stdout.

sed 's/\\n/\
/g' file.txt | awk 'NR==10{print}'