smallest checksum on a string

Question

scratching my head over this.

i have 350 strings average 90 chars long, all strings are unique. Now, i wanna generate a unique id for each string.

i tried the sum of chars in the string wich gave two doubles, the returned sum is not unique enough. Anybody any idea how to approach this? I thought of hash(), is that the best solution?

abcdef will return the same as abcdfe

Answer 1

Checksums and hashes will never be unique. Call the first string "1" and go from there.

Answer 2

If you have a fixed set of strings and you will only need to look those up then find a minimal perfect hash function. http://en.wikipedia.org/wiki/Perfect_hash_function