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old_snippets/remove-common-lines.en.md

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+---
+title: "remove common lines with comm"
+seo_description: "How to remove common lines from files using the comm command"
+date: 2023-05-24T12:52:11+02:00
+draft: false
+snippet_types:
+- comm
+---
+
+With help of ChatGPT I discovered this unix gem today. 
+
+Given two files 
+
+main_deck.txt:
+```
+1 Abzan Charm
+1 Arcane Bombardment
+1 Arcane Sanctum
+1 Arcane Signet
+1 Archmage Emeritus
+1 Bant Charm
+1 Boros Charm
+1 Bring to Light
+1 Brokers Charm
+1 Brokers Confluence
+```
+
+considering.txt:
+```
+1 Abzan Charm
+1 Arcane Sanctum
+1 Taigam, Ojutai Master
+1 Archmage Emeritus
+1 Boros Charm
+1 Tamanoa
+1 Time Wipe
+1 Trap Essence
+1 Brokers Confluence
+```
+
+running 
+
+```shell
+$ comm -23 <(cat considering.txt | sort) <(cat main_deck.txt | sort)
+1 Taigam, Ojutai Master
+1 Tamanoa
+1 Time Wipe
+1 Trap Essence
+```
+
+Returns a list of cards that are unique to the considering.txt.
+
+If your text files are sorted you can skip the `<(cat ..)` magic.
+
+And yes. I'm using the cli two help build Magic the Gathering Decks!