Perl脚本比较两个文件，但按顺序打印

Question

I have followed this question perl compare two file and print the matching lines and found lines which match or dont match between two files using hash.

But I find that hash rearranges the lines and I want the lines in order. I can write multiple for loops to get results in order but this is not as efficient as hash. Has anyone faced this issue before and could please help with their solution

Answer 1

Maybe don't understand fully the question but

fgrep -xf file2 file1

is not enough?

or

fgrep -xf file1 file2

yes, it is not perl but, short simple and fast...

Answer 2

This can be done efficiently in two steps. Let's assume you have been able to find the "lines that match" but they are in the wrong order; then a simple grep can re-organize them. Assuming you have a script matchThem that takes two inputs ( file1 and file2 ) and outputs them to tempFile , then the over all script will be:

matchThem file1 file2 > tempFile
grep -Fx -f tempFile file1

The -Fx flag means:

-F : find exact match only (much faster than wildcards)
-x : only match whole lines

Answer 3

如果要保留插入顺序的哈希，请尝试使用CPAN模块Tie :: IxHash 。