M.V. Hutz
6a5b40c097
- Removed instances of `growthFactor`, as it is unexported. - Typo in `HashTable.String()`.
104 lines
1.9 KiB
Go
104 lines
1.9 KiB
Go
package cuckoo
|
|
|
|
type entry[K, V any] struct {
|
|
key K
|
|
value V
|
|
}
|
|
|
|
type slot[K, V any] struct {
|
|
entry[K, V]
|
|
occupied bool
|
|
}
|
|
|
|
type table[K, V any] struct {
|
|
hash Hash[K]
|
|
slots []slot[K, V]
|
|
capacity, size uint64
|
|
compare EqualFunc[K]
|
|
}
|
|
|
|
// location determines where in the table a certain key would be placed. If the
|
|
// capacity is 0, this will panic.
|
|
func (t table[K, V]) location(key K) uint64 {
|
|
return t.hash(key) % t.capacity
|
|
}
|
|
|
|
func (t table[K, V]) get(key K) (value V, found bool) {
|
|
if t.capacity == 0 {
|
|
return
|
|
}
|
|
|
|
slot := t.slots[t.location(key)]
|
|
return slot.value, slot.occupied && t.compare(slot.key, key)
|
|
}
|
|
|
|
func (t *table[K, V]) drop(key K) (occupied bool) {
|
|
if t.capacity == 0 {
|
|
return
|
|
}
|
|
|
|
slot := &t.slots[t.location(key)]
|
|
|
|
if slot.occupied && t.compare(slot.key, key) {
|
|
slot.occupied = false
|
|
t.size--
|
|
return true
|
|
}
|
|
|
|
return false
|
|
}
|
|
|
|
func (t *table[K, V]) resize(capacity uint64) {
|
|
t.slots = make([]slot[K, V], capacity)
|
|
t.capacity = capacity
|
|
t.size = 0
|
|
}
|
|
|
|
func (t table[K, V]) update(key K, value V) (updated bool) {
|
|
if t.capacity == 0 {
|
|
return
|
|
}
|
|
|
|
slot := &t.slots[t.location(key)]
|
|
|
|
if slot.occupied && t.compare(slot.key, key) {
|
|
slot.value = value
|
|
return true
|
|
}
|
|
|
|
return false
|
|
}
|
|
|
|
func (t *table[K, V]) evict(insertion entry[K, V]) (evicted entry[K, V], eviction bool) {
|
|
if t.capacity == 0 {
|
|
return insertion, true
|
|
}
|
|
|
|
slot := &t.slots[t.location(insertion.key)]
|
|
|
|
if !slot.occupied {
|
|
slot.entry = insertion
|
|
slot.occupied = true
|
|
t.size++
|
|
return
|
|
}
|
|
|
|
if t.compare(slot.key, insertion.key) {
|
|
slot.value = insertion.value
|
|
return
|
|
}
|
|
|
|
insertion, slot.entry = slot.entry, insertion
|
|
return insertion, true
|
|
}
|
|
|
|
func newTable[K, V any](capacity uint64, hash Hash[K], compare EqualFunc[K]) table[K, V] {
|
|
return table[K, V]{
|
|
hash: hash,
|
|
capacity: capacity,
|
|
compare: compare,
|
|
size: 0,
|
|
slots: make([]slot[K, V], capacity),
|
|
}
|
|
}
|