avl insertion

avl_test.go

@@ -0,0 +1,88 @@
+package avl
+
+import (
+	"bytes"
+	"fmt"
+	"testing"
+)
+
+type testKey int
+
+func (k testKey) Compare(c Comparable) int {
+	var (
+		ck testKey
+		ok bool
+	)
+
+	if ck, ok = c.(testKey); !ok {
+		panic("unexpected type")
+	}
+
+	return int(k - ck)
+}
+
+func (k testKey) String() string {
+	return fmt.Sprintf("%d", int(k))
+}
+
+func preOrder(b *bytes.Buffer, node *Node) {
+	if node != nil {
+		_, _ = fmt.Fprint(b, node.key, " ")
+		preOrder(b, node.left)
+		preOrder(b, node.right)
+	}
+}
+
+func TestInsert(t *testing.T) {
+	var (
+		root *Node
+		b    *bytes.Buffer
+	)
+
+	root = Insert(root, testKey(10))
+	root = Insert(root, testKey(20))
+	root = Insert(root, testKey(30))
+	root = Insert(root, testKey(40))
+	root = Insert(root, testKey(50))
+	root = Insert(root, testKey(25))
+
+	b = bytes.NewBuffer([]byte{})
+	preOrder(b, root)
+
+	//The constructed AVL Tree would be
+	//        30
+	//       /  \
+	//     20   40
+	//    /  \     \
+	//   10  25    50
+
+	t.Log("preorder traversal of the tree")
+	t.Log(b)
+}
+
+func TestInsert2(t *testing.T) {
+	var (
+		tree *Tree
+		keys = []testKey{10, 20, 25, 30, 40, 50}
+		out  []Comparable
+	)
+
+	tree = new(Tree)
+	tree.Insert(keys[0])
+	tree.Insert(keys[1])
+	tree.Insert(keys[3])
+	tree.Insert(keys[4])
+	tree.Insert(keys[5])
+	tree.Insert(keys[2])
+
+	out = tree.Slice()
+	for i, k := range out {
+		if ck, ok := k.(testKey); ok {
+			if ck != keys[i] {
+				t.Fatal("mismatch data")
+			}
+		} else {
+			t.Fatal("invalid data type")
+		}
+	}
+}