algorithm - Removing duplicate strings with limited memory -



algorithm - Removing duplicate strings with limited memory -

say have list of strings , can't load entire list in memory, can load parts of list file. best way solve this?

one approach utilize external sort sort file, , remove duplicates single iteration on sorted list. approach requries little space , o(nlogn) accesses disk.

another approach based on hashing: utilize hashcode of string, , load sublist contains strings whom hashcode in specific range. guaranteed if x loaded, , has duplicate - dupe loaded same bucket well. this requires o(n*#buckets) accesses disk, might require more memory. can invoke procedure recursively (with different hash functions) if needed.

algorithm data-structures

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