diff --git a/heap/heap.go b/heap/heap.go
new file mode 100644
index 0000000..35c27ff
--- /dev/null
+++ b/heap/heap.go
@@ -0,0 +1,16 @@
+package heap
+
+import (
+	"474420502.top/eson/structure/compare"
+)
+
+type Heap struct {
+	size     int
+	cap      int
+	elements []interface{}
+	Compare  compare.Compare
+}
+
+func New(Compare compare.Compare) *Heap {
+	return &Heap{Compare: Compare, cap: 8}
+}
diff --git a/sparse_array/array2.go b/sparse_array/array2.go
new file mode 100644
index 0000000..40f049f
--- /dev/null
+++ b/sparse_array/array2.go
@@ -0,0 +1,93 @@
+package sparse
+
+type Array2 struct {
+	sizes []int
+	ysize int
+	xsize int
+	data  [][]interface{}
+}
+
+func New() *Array2 {
+	arr := &Array2{ysize: 8, xsize: 8}
+	arr.sizes = make([]int, arr.ysize, arr.ysize)
+	arr.data = make([][]interface{}, arr.ysize, arr.ysize)
+	return arr
+}
+
+func NewWithCap(ysize, xsize int) *Array2 {
+	arr := &Array2{ysize: ysize, xsize: xsize}
+	arr.sizes = make([]int, arr.ysize, arr.ysize)
+	arr.data = make([][]interface{}, arr.ysize, arr.ysize)
+	return arr
+}
+
+func (arr *Array2) Values() []interface{} {
+	var result []interface{}
+	for _, y := range arr.data {
+		if y != nil {
+			for _, v := range y {
+				if v == nil {
+					result = append(result, struct{}{})
+				} else {
+					result = append(result, v)
+				}
+			}
+		} else {
+			for i := 0; i < arr.ysize; i++ {
+				result = append(result, nil)
+			}
+		}
+	}
+
+	return result
+}
+
+func (arr *Array2) Set(idx int, value interface{}) {
+	yindex := idx / arr.ysize
+	xindex := idx % arr.xsize
+
+	ydata := arr.data[yindex]
+	if ydata == nil {
+		ydata = make([]interface{}, arr.xsize, arr.xsize)
+		arr.data[yindex] = ydata
+	}
+
+	if ydata[xindex] == nil {
+		arr.sizes[yindex]++
+	}
+
+	ydata[xindex] = value
+}
+
+func (arr *Array2) Get(idx int) (interface{}, bool) {
+	yindex := idx / arr.ysize
+	xindex := idx % arr.xsize
+
+	ydata := arr.data[yindex]
+	if ydata == nil {
+		return nil, false
+	}
+	v := ydata[xindex]
+	return v, v != nil
+}
+
+func (arr *Array2) Del(idx int) (interface{}, bool) {
+	yindex := idx / arr.ysize
+	xindex := idx % arr.xsize
+
+	ydata := arr.data[yindex]
+	if ydata == nil {
+		return nil, false
+	}
+	v := ydata[xindex]
+	ydata[xindex] = nil
+
+	isnil := v != nil
+	if isnil {
+		arr.sizes[yindex]--
+		if arr.sizes[yindex] == 0 {
+			arr.data[yindex] = nil
+		}
+	}
+	return v, isnil
+}
diff --git a/sparse_array/array2_test.go b/sparse_array/array2_test.go
new file mode 100644
index 0000000..43ec894
--- /dev/null
+++ b/sparse_array/array2_test.go
@@ -0,0 +1,154 @@
+package sparse
+
+import (
+	"testing"
+
+	"github.com/davecgh/go-spew/spew"
+
+	"github.com/Pallinder/go-randomdata"
+)
+
+func TestSet(t *testing.T) {
+	arr := NewWithCap(4, 4)
+	l := []int{0, 6, 5, 15}
+	for _, v := range l {
+		arr.Set(v, v)
+	}
+
+	var result string
+	result = spew.Sprint(arr.Values())
+	if result != "[0 {} {} {} {} 5 6 {} <nil> <nil> <nil> <nil> {} {} {} 15]" {
+		t.Error(result)
+	}
+
+	defer func() {
+		if err := recover(); err == nil {
+			t.Error("err == nil, but array the set is out of range")
+		}
+	}()
+
+	arr.Set(16, 16)
+}
+
+func TestGet(t *testing.T) {
+	arr := New()
+	for i := 0; i < 64; i++ {
+		arr.Set(i, i)
+	}
+
+	for i := 0; i < 64; i++ {
+		if v, ok := arr.Get(i); ok {
+			if v != i {
+				t.Error("v is equal i, but", v, i)
+			}
+		} else {
+			t.Error("not ok is error")
+		}
+	}
+
+	defer func() {
+		if err := recover(); err == nil {
+			t.Error("err == nil, but array the get is out of range")
+		}
+	}()
+
+	arr.Get(64)
+}
+
+func TestDel(t *testing.T) {
+	arr := NewWithCap(4, 4)
+	l := []int{0, 6, 5, 15}
+	for _, v := range l {
+		arr.Set(v, v)
+	}
+	// default  [0 {} {} {} {} 5 6 {} <nil> <nil> <nil> <nil> {} {} {} 15]
+	var result string
+
+	arr.Del(0)
+	result = spew.Sprint(arr.Values())
+	if result != "[<nil> <nil> <nil> <nil> {} 5 6 {} <nil> <nil> <nil> <nil> {} {} {} 15]" {
+		t.Error(result)
+	}
+
+	arr.Del(5)
+	result = spew.Sprint(arr.Values())
+	if result != "[<nil> <nil> <nil> <nil> {} {} 6 {} <nil> <nil> <nil> <nil> {} {} {} 15]" {
+		t.Error(result)
+	}
+
+	arr.Del(6)
+	result = spew.Sprint(arr.Values())
+	if result != "[<nil> <nil> <nil> <nil> <nil> <nil> <nil> <nil> <nil> <nil> <nil> <nil> {} {} {} 15]" {
+		t.Error(result)
+	}
+
+	arr.Del(15)
+	result = spew.Sprint(arr.Values())
+	if result != "[<nil> <nil> <nil> <nil> <nil> <nil> <nil> <nil> <nil> <nil> <nil> <nil> <nil> <nil> <nil> <nil>]" {
+		t.Error(result)
+	}
+
+	defer func() {
+		if err := recover(); err == nil {
+			t.Error("err == nil, but array the del is out of range")
+		}
+	}()
+
+	arr.Del(16)
+}
+
+func BenchmarkSet(b *testing.B) {
+
+	arr := NewWithCap(1000, 100)
+	b.N = 500000000
+
+	b.StopTimer()
+	var l []int
+	for i := 0; i < b.N/10; i++ {
+		l = append(l, randomdata.Number(0, 65535))
+	}
+	b.StartTimer()
+	for c := 0; c < 10; c++ {
+		for i := 0; i < b.N/10; i++ {
+			arr.Set(l[i], i)
+		}
+	}
+
+}
+
+func BenchmarkGet(b *testing.B) {
+
+	arr := NewWithCap(1000, 100)
+	b.N = 500000000
+
+	b.StopTimer()
+
+	for i := 0; i < 105535; i++ {
+		v := randomdata.Number(0, 65535)
+		arr.Set(v, v)
+	}
+	b.StartTimer()
+
+	for i := 0; i < b.N; i++ {
+		arr.Get(i % 65535)
+	}
+
+}
+
+func BenchmarkDel(b *testing.B) {
+
+	arr := NewWithCap(1000, 100)
+	b.N = 500000000
+
+	b.StopTimer()
+	for i := 0; i < 105535; i++ {
+		v := randomdata.Number(0, 65535)
+		arr.Set(v, v)
+	}
+	b.StartTimer()
+
+	for i := 0; i < b.N; i++ {
+		arr.Del(i % 65535)
+	}
+
+}