Content-addressable store

A content-addressable store deduplicates blobs: two blobs with identical content are stored once. You are given a list of blob contents (each a string). The store addresses each blob by a content hash defined deterministically as follows: h = 1469598103934665603; for each byte b of the UTF-8 encoding of the content, h = ((h XOR b) * 1099511628211) mod 2**64 (this is 64-bit FNV-1a). Two blobs collide-free iff their hashes differ; treat equal hashes as the same content. Each unique hash is stored exactly once and occupies len(content) bytes. Return the total number of bytes the store occupies after ingesting all blobs (sum of content lengths over unique hashes only). Up to 10^5 blobs.