어제의 인벤토리와 오늘의 인벤토리를 직접 비교하는 명령은 무엇인가요?
cat inventory-check/today.txt inventory-check/today.txt
diff inventory-check/yesterday.txt inventory-check/today.txt
cp inventory-check/today.txt inventory-check/yesterday.txt
rm inventory-check/yesterday.txt