map

Author: gbember

test/m.go

@@ -0,0 +1,101 @@
+package test
+
+// Deal的定义
+type DealTiny struct {
+	Dealid    int32
+	Classid   int32
+	Mttypeid  int32
+	Bizacctid int32
+	Isonline  bool
+	Geocnt    int32
+}
+
+type DealMap struct {
+	table   []DealTiny
+	buckets int
+	size    int
+}
+
+// round 到最近的2的倍数
+func minBuckets(v int) int {
+	v--
+	v |= v >> 1
+	v |= v >> 2
+	v |= v >> 4
+	v |= v >> 8
+	v |= v >> 16
+	v++
+	return v
+}
+
+func hashInt32(x int) int {
+	x = ((x >> 16) ^ x) * 0x45d9f3b
+	x = ((x >> 16) ^ x) * 0x45d9f3b
+	x = ((x >> 16) ^ x)
+	return x
+}
+
+func NewDealMap(maxsize int) *DealMap {
+	buckets := minBuckets(maxsize)
+	return &DealMap{size: 0, buckets: buckets, table: make([]DealTiny, buckets)}
+}
+
+// TODO rehash策略
+func (m *DealMap) Put(d DealTiny) {
+	num_probes, bucket_count_minus_one := 0, m.buckets-1
+	bucknum := hashInt32(int(d.Dealid)) & bucket_count_minus_one
+	for {
+		if m.table[bucknum].Dealid == 0 { // insert, 不支持放入ID为0的Deal
+			m.size += 1
+			m.table[bucknum] = d
+			return
+		}
+		if m.table[bucknum].Dealid == d.Dealid { // update
+			m.table[bucknum] = d
+			return
+		}
+		num_probes += 1 // Open addressing with Linear probing
+		bucknum = (bucknum + num_probes) & bucket_count_minus_one
+	}
+}
+
+func (m *DealMap) Get(id int32) (DealTiny, bool) {
+	num_probes, bucket_count_minus_one := 0, m.buckets-1
+	bucknum := hashInt32(int(id)) & bucket_count_minus_one
+	for {
+		if m.table[bucknum].Dealid == id {
+			return m.table[bucknum], true
+		}
+		if m.table[bucknum].Dealid == 0 {
+			return m.table[bucknum], false
+		}
+		num_probes += 1
+		bucknum = (bucknum + num_probes) & bucket_count_minus_one
+	}
+}
+
+func (m *DealMap) Delete(id int32) (DealTiny, bool) {
+	num_probes, bucket_count_minus_one := 0, m.buckets-1
+	bucknum := hashInt32(int(id)) & bucket_count_minus_one
+	for {
+		if m.table[bucknum].Dealid == id {
+			deal := m.table[bucknum]
+			num_probes += 1
+			bucknum1 := bucknum
+			bucknum2 := (bucknum + num_probes) & bucket_count_minus_one
+			for bucknum2 < m.buckets && m.table[bucknum2].Dealid != 0 {
+				m.table[bucknum1] = m.table[bucknum2]
+				bucknum1 = bucknum2
+				num_probes += 1
+				bucknum2 = (bucknum + num_probes) & bucket_count_minus_one
+			}
+			m.table[bucknum1].Dealid = 0
+			return deal, true
+		}
+		if m.table[bucknum].Dealid == 0 {
+			return m.table[bucknum], false
+		}
+		num_probes += 1
+		bucknum = (bucknum + num_probes) & bucket_count_minus_one
+	}
+}