From 3ef4f4d134d23f65f58aae18e51d3518927c3443 Mon Sep 17 00:00:00 2001
From: eson <474420502@qq.com>
Date: Sun, 7 Apr 2019 04:43:03 +0800
Subject: [PATCH] =?UTF-8?q?=E5=8A=A0=E5=BC=BA=E5=8F=AF=E8=AF=BB=E6=80=A7?=
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---
 priority_queue/vbt.go | 66 ++++++++++++++++++-------------------------
 1 file changed, 28 insertions(+), 38 deletions(-)

diff --git a/priority_queue/vbt.go b/priority_queue/vbt.go
index feb9a0f..4873659 100644
--- a/priority_queue/vbt.go
+++ b/priority_queue/vbt.go
@@ -624,37 +624,41 @@ func (tree *vbTree) Traversal(every func(v interface{}) bool, traversalMethod ..
 	}
 }
 
+func setChild(cur *tNode, cidx int, child *tNode) {
+	cur.children[cidx] = child
+	cur.children[cidx].parent = cur
+}
+
+func (tree *vbTree) replaceParent(old, new *tNode) {
+	if old.parent == nil {
+		tree.root = new
+	} else {
+		if old.parent.children[1] == old {
+			old.parent.children[1] = new
+		} else {
+			old.parent.children[0] = new
+		}
+	}
+	new.parent = old.parent
+}
+
 func (tree *vbTree) lrrotate3(cur *tNode) *tNode {
 	const l = 1
 	const r = 0
 
 	ln := cur.children[l]
+	cur.children[l] = nil
+
 	lrn := ln.children[r]
 	ln.children[r] = nil
 
-	if cur.parent == nil {
-		tree.root = lrn
-	} else {
-		if cur.parent.children[1] == cur {
-			cur.parent.children[1] = lrn
-		} else {
-			cur.parent.children[0] = lrn
-		}
-	}
-	lrn.parent = cur.parent
-
-	lrn.children[l] = cur.children[l]
-	lrn.children[l].parent = lrn
-
-	lrn.children[r] = cur
-	lrn.children[r].parent = lrn
-
-	cur.children[l] = nil
+	tree.replaceParent(cur, lrn)
+	setChild(lrn, l, ln)
+	setChild(lrn, r, cur)
 
 	lrn.size = 3
 	lrn.children[l].size = 1
 	lrn.children[r].size = 1
-
 	return lrn
 }
 
@@ -703,32 +707,18 @@ func (tree *vbTree) rlrotate3(cur *tNode) *tNode {
 	const r = 1
 
 	ln := cur.children[l]
+	cur.children[l] = nil
+
 	lrn := ln.children[r]
 	ln.children[r] = nil
 
-	if cur.parent == nil {
-		tree.root = lrn
-	} else {
-		if cur.parent.children[1] == cur {
-			cur.parent.children[1] = lrn
-		} else {
-			cur.parent.children[0] = lrn
-		}
-	}
-	lrn.parent = cur.parent
-
-	lrn.children[l] = cur.children[l]
-	lrn.children[l].parent = lrn
-
-	lrn.children[r] = cur
-	lrn.children[r].parent = lrn
-
-	cur.children[l] = nil
+	tree.replaceParent(cur, lrn)
+	setChild(lrn, l, ln)
+	setChild(lrn, r, cur)
 
 	lrn.size = 3
 	lrn.children[l].size = 1
 	lrn.children[r].size = 1
-
 	return lrn
 }