Shared SKU Prefix

easy

A warehouse labels products with SKU strings, and codes from the same supplier share a leading stem — "FORGE-ANVIL-01", "FORGE-ANVIL-02", "FORGE-TONGS-01" all start with "FORGE-". Given a batch of codes, the intake scanner wants that stem.

Return the longest common prefix of all strings in codes. If they share nothing, return the empty string "".

Example 1

in codes = ["flower", "flow", "flight"]

out "fl"

All three open with "fl"; the third letter diverges (o vs i).

Example 2

in codes = ["dog", "racecar", "car"]

out ""

No shared first letter, so no shared stem at all.

Constraints

· 1 <= len(codes) <= 200
· 0 <= len(codes[i]) <= 200
· codes[i] consists of printable ASCII characters