[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.

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給定一個文本文件 file.txt，請只打印這個文件中的第十行。

示例:

假設 file.txt 有以下內容：

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

你的腳本應當顯示第十行：

Line 10

說明:
1. 若是文件少於十行，你應當輸出什麼？
2. 至少有三種不一樣的解法，請嘗試儘量多的方法來解題。

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 4ms

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

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4ms

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

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8ms

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

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12ms

1 # Read from the file file.txt and output the tenth line to stdout.
2 
3 sed 's/\\n/\
4 /g' file.txt | awk 'NR==10{print}'