Use absolute value of hash as bucket #12
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timtadh
requested changes
Jul 15, 2022
hashtable/hashtable.go
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| @@ -57,7 +65,7 @@ func NewHashTable(initial_size int) *Hash { | |||
| } | |||
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| func (self *Hash) bucket(key Hashable) int { | |||
| return key.Hash() % len(self.table) | |||
| return abs(key.Hash() % len(self.table)) | |||
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Suggested change
| return abs(key.Hash() % len(self.table)) | |
| return abs(key.Hash()) % len(self.table) |
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It makes more sense this way indeed.
On 32 bits architechtures, string hashes tend to have negative values. Such values cannot be used as bucket identifiers for hashtables. Using absolute value in case of negative hash solves this issue. Signed-off-by: Julien Rische <[email protected]>
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On 32 bits architechtures, string hashes tend to have negative values.
Such values cannot be used as bucket identifiers for hashtables:
Using absolute value in case of negative hash solves this issue.