Hello Monks!
Perl newbie here, and I am faced with the following problem:
I have 2 files with likes like the following: 
FILE1
ID1:6qq5_A|14~~6qq5_B|14~~6qq6_A|14~~6qq6_B|14~~6t6v_A|14
ID2:7d5p_A|14~~7d5q_A|14

FILE2
ID1:6qq5_A|15~~6qq5_B|15~~6qq6_A|14~~6qq6_B|15~~6t6v_A|14
ID2:7d5p_A|14~~7d5q_A|12

[download]

basically, common ids, like ID1 and ID2 and then, next to them, a series of strings like 6t6v_A|14 separated by ~~. Now, what I need to do is, check, for each of the IDS (in this example ID1 and ID2), which of these smaller strings are the same. In my example, the desired output would be: 
ID1:6t6v_A|14
ID1:6qq6_A|14
ID2:7d5p_A|14

[download]

because these are the only commons strings for each of the two IDs. What I am planning to do is create an structure like AoA and compare each of the elements, sequentially, to see which ones are the same. Is there maybe a faster way to do this task? Any pointers/help would be greatly appreciated!

In reply to Find common substrings by Anonymous Monk

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