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-rw-r--r--src/livarot/AVL.cpp969
1 files changed, 969 insertions, 0 deletions
diff --git a/src/livarot/AVL.cpp b/src/livarot/AVL.cpp
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+++ b/src/livarot/AVL.cpp
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+// SPDX-License-Identifier: GPL-2.0-or-later
+/** @file
+ * TODO: insert short description here
+ *//*
+ * Authors:
+ * see git history
+ * Fred
+ *
+ * Copyright (C) 2018 Authors
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include "AVL.h"
+
+/*
+ * the algorithm explanation for this code comes from purists.org, which seems to have disappeared since
+ * it's a classic AVL tree rebalancing, nothing fancy
+ */
+
+AVLTree::AVLTree()
+{
+ MakeNew();
+}
+
+AVLTree::~AVLTree()
+{
+ MakeDelete();
+}
+
+void AVLTree::MakeNew()
+{
+ for (int i = 0; i < 2; i++)
+ {
+ elem[i] = nullptr;
+ child[i] = nullptr;
+ }
+
+ parent = nullptr;
+ balance = 0;
+}
+
+void AVLTree::MakeDelete()
+{
+ for (int i = 0; i < 2; i++) {
+ if (elem[i]) {
+ elem[i]->elem[1 - i] = elem[1 - i];
+ }
+ elem[i] = nullptr;
+ }
+}
+
+AVLTree *AVLTree::Leftmost()
+{
+ return leafFromParent(nullptr, LEFT);
+}
+
+AVLTree *AVLTree::leaf(AVLTree *from, Side s)
+{
+ if (from == child[1 - s]) {
+ if (child[s]) {
+ return child[s]->leafFromParent(this, s);
+ }
+ else if (parent) {
+ return parent->leaf(this, s);
+ }
+ }
+ else if (from == child[s]) {
+ if (parent) {
+ return parent->leaf(this, s);
+ }
+ }
+
+ return nullptr;
+}
+
+AVLTree *AVLTree::leafFromParent(AVLTree */*from*/, Side s)
+{
+ if (child[s]) {
+ return child[s]->leafFromParent(this, s);
+ }
+
+ return this;
+}
+
+int
+AVLTree::RestoreBalances (AVLTree * from, AVLTree * &racine)
+{
+ if (from == nullptr)
+ {
+ if (parent)
+ return parent->RestoreBalances (this, racine);
+ }
+ else
+ {
+ if (balance == 0)
+ {
+ if (from == child[LEFT])
+ balance = 1;
+ if (from == child[RIGHT])
+ balance = -1;
+ if (parent)
+ return parent->RestoreBalances (this, racine);
+ return avl_no_err;
+ }
+ else if (balance > 0)
+ {
+ if (from == child[RIGHT])
+ {
+ balance = 0;
+ return avl_no_err;
+ }
+ if (child[LEFT] == nullptr)
+ {
+// cout << "mierda\n";
+ return avl_bal_err;
+ }
+ AVLTree *a = this;
+ AVLTree *b = child[LEFT];
+ AVLTree *e = child[RIGHT];
+ AVLTree *c = child[LEFT]->child[LEFT];
+ AVLTree *d = child[LEFT]->child[RIGHT];
+ if (child[LEFT]->balance > 0)
+ {
+ AVLTree *r = parent;
+
+ a->parent = b;
+ b->child[RIGHT] = a;
+ a->child[RIGHT] = e;
+ if (e)
+ e->parent = a;
+ a->child[LEFT] = d;
+ if (d)
+ d->parent = a;
+ b->child[LEFT] = c;
+ if (c)
+ c->parent = b;
+ b->parent = r;
+ if (r)
+ {
+ if (r->child[LEFT] == a)
+ r->child[LEFT] = b;
+ if (r->child[RIGHT] == a)
+ r->child[RIGHT] = b;
+ }
+ if (racine == a)
+ racine = b;
+
+ a->balance = 0;
+ b->balance = 0;
+ return avl_no_err;
+ }
+ else
+ {
+ if (child[LEFT]->child[RIGHT] == nullptr)
+ {
+ // cout << "mierda\n";
+ return avl_bal_err;
+ }
+ AVLTree *f = child[LEFT]->child[RIGHT]->child[LEFT];
+ AVLTree *g = child[LEFT]->child[RIGHT]->child[RIGHT];
+ AVLTree *r = parent;
+
+ a->parent = d;
+ d->child[RIGHT] = a;
+ b->parent = d;
+ d->child[LEFT] = b;
+ a->child[LEFT] = g;
+ if (g)
+ g->parent = a;
+ a->child[RIGHT] = e;
+ if (e)
+ e->parent = a;
+ b->child[LEFT] = c;
+ if (c)
+ c->parent = b;
+ b->child[RIGHT] = f;
+ if (f)
+ f->parent = b;
+
+ d->parent = r;
+ if (r)
+ {
+ if (r->child[LEFT] == a)
+ r->child[LEFT] = d;
+ if (r->child[RIGHT] == a)
+ r->child[RIGHT] = d;
+ }
+ if (racine == a)
+ racine = d;
+
+ int old_bal = d->balance;
+ d->balance = 0;
+ if (old_bal == 0)
+ {
+ a->balance = 0;
+ b->balance = 0;
+ }
+ else if (old_bal > 0)
+ {
+ a->balance = -1;
+ b->balance = 0;
+ }
+ else if (old_bal < 0)
+ {
+ a->balance = 0;
+ b->balance = 1;
+ }
+ return avl_no_err;
+ }
+ }
+ else if (balance < 0)
+ {
+ if (from == child[LEFT])
+ {
+ balance = 0;
+ return avl_no_err;
+ }
+ if (child[RIGHT] == nullptr)
+ {
+// cout << "mierda\n";
+ return avl_bal_err;
+ }
+ AVLTree *a = this;
+ AVLTree *b = child[RIGHT];
+ AVLTree *e = child[LEFT];
+ AVLTree *c = child[RIGHT]->child[RIGHT];
+ AVLTree *d = child[RIGHT]->child[LEFT];
+ AVLTree *r = parent;
+ if (child[RIGHT]->balance < 0)
+ {
+
+ a->parent = b;
+ b->child[LEFT] = a;
+ a->child[LEFT] = e;
+ if (e)
+ e->parent = a;
+ a->child[RIGHT] = d;
+ if (d)
+ d->parent = a;
+ b->child[RIGHT] = c;
+ if (c)
+ c->parent = b;
+ b->parent = r;
+ if (r)
+ {
+ if (r->child[LEFT] == a)
+ r->child[LEFT] = b;
+ if (r->child[RIGHT] == a)
+ r->child[RIGHT] = b;
+ }
+ if (racine == a)
+ racine = b;
+ a->balance = 0;
+ b->balance = 0;
+ return avl_no_err;
+ }
+ else
+ {
+ if (child[RIGHT]->child[LEFT] == nullptr)
+ {
+// cout << "mierda\n";
+ return avl_bal_err;
+ }
+ AVLTree *f = child[RIGHT]->child[LEFT]->child[RIGHT];
+ AVLTree *g = child[RIGHT]->child[LEFT]->child[LEFT];
+
+ a->parent = d;
+ d->child[LEFT] = a;
+ b->parent = d;
+ d->child[RIGHT] = b;
+ a->child[RIGHT] = g;
+ if (g)
+ g->parent = a;
+ a->child[LEFT] = e;
+ if (e)
+ e->parent = a;
+ b->child[RIGHT] = c;
+ if (c)
+ c->parent = b;
+ b->child[LEFT] = f;
+ if (f)
+ f->parent = b;
+
+ d->parent = r;
+ if (r)
+ {
+ if (r->child[LEFT] == a)
+ r->child[LEFT] = d;
+ if (r->child[RIGHT] == a)
+ r->child[RIGHT] = d;
+ }
+ if (racine == a)
+ racine = d;
+ int old_bal = d->balance;
+ d->balance = 0;
+ if (old_bal == 0)
+ {
+ a->balance = 0;
+ b->balance = 0;
+ }
+ else if (old_bal > 0)
+ {
+ a->balance = 0;
+ b->balance = -1;
+ }
+ else if (old_bal < 0)
+ {
+ a->balance = 1;
+ b->balance = 0;
+ }
+ return avl_no_err;
+ }
+ }
+ }
+ return avl_no_err;
+}
+
+int
+AVLTree::RestoreBalances (int diff, AVLTree * &racine)
+{
+ if (balance > 0)
+ {
+ if (diff < 0)
+ {
+ balance = 0;
+ if (parent)
+ {
+ if (this == parent->child[RIGHT])
+ return parent->RestoreBalances (1, racine);
+ if (this == parent->child[LEFT])
+ return parent->RestoreBalances (-1, racine);
+ }
+ return avl_no_err;
+ }
+ else if (diff == 0)
+ {
+ }
+ else if (diff > 0)
+ {
+ if (child[LEFT] == nullptr)
+ {
+// cout << "un probleme\n";
+ return avl_bal_err;
+ }
+ AVLTree *r = parent;
+ AVLTree *a = this;
+ AVLTree *b = child[RIGHT];
+ AVLTree *e = child[LEFT];
+ AVLTree *f = e->child[RIGHT];
+ AVLTree *g = e->child[LEFT];
+ if (e->balance > 0)
+ {
+ e->child[RIGHT] = a;
+ e->child[LEFT] = g;
+ a->child[RIGHT] = b;
+ a->child[LEFT] = f;
+ if (a)
+ a->parent = e;
+ if (g)
+ g->parent = e;
+ if (b)
+ b->parent = a;
+ if (f)
+ f->parent = a;
+ e->parent = r;
+ if (r)
+ {
+ if (r->child[LEFT] == a)
+ r->child[LEFT] = e;
+ if (r->child[RIGHT] == a)
+ r->child[RIGHT] = e;
+ }
+ if (racine == this)
+ racine = e;
+ e->balance = 0;
+ a->balance = 0;
+ if (r)
+ {
+ if (e == r->child[RIGHT])
+ return r->RestoreBalances (1, racine);
+ if (e == r->child[LEFT])
+ return r->RestoreBalances (-1, racine);
+ }
+ return avl_no_err;
+ }
+ else if (e->balance == 0)
+ {
+ e->child[RIGHT] = a;
+ e->child[LEFT] = g;
+ a->child[RIGHT] = b;
+ a->child[LEFT] = f;
+ if (a)
+ a->parent = e;
+ if (g)
+ g->parent = e;
+ if (b)
+ b->parent = a;
+ if (f)
+ f->parent = a;
+ e->parent = r;
+ if (r)
+ {
+ if (r->child[LEFT] == a)
+ r->child[LEFT] = e;
+ if (r->child[RIGHT] == a)
+ r->child[RIGHT] = e;
+ }
+ if (racine == this)
+ racine = e;
+ e->balance = -1;
+ a->balance = 1;
+ return avl_no_err;
+ }
+ else if (e->balance < 0)
+ {
+ if (child[LEFT]->child[RIGHT] == nullptr)
+ {
+// cout << "un probleme\n";
+ return avl_bal_err;
+ }
+ AVLTree *i = child[LEFT]->child[RIGHT]->child[RIGHT];
+ AVLTree *j = child[LEFT]->child[RIGHT]->child[LEFT];
+
+ f->child[RIGHT] = a;
+ f->child[LEFT] = e;
+ a->child[RIGHT] = b;
+ a->child[LEFT] = i;
+ e->child[RIGHT] = j;
+ e->child[LEFT] = g;
+ if (b)
+ b->parent = a;
+ if (i)
+ i->parent = a;
+ if (g)
+ g->parent = e;
+ if (j)
+ j->parent = e;
+ if (a)
+ a->parent = f;
+ if (e)
+ e->parent = f;
+ f->parent = r;
+ if (r)
+ {
+ if (r->child[LEFT] == a)
+ r->child[LEFT] = f;
+ if (r->child[RIGHT] == a)
+ r->child[RIGHT] = f;
+ }
+ if (racine == this)
+ racine = f;
+ int oBal = f->balance;
+ f->balance = 0;
+ if (oBal > 0)
+ {
+ a->balance = -1;
+ e->balance = 0;
+ }
+ else if (oBal == 0)
+ {
+ a->balance = 0;
+ e->balance = 0;
+ }
+ else if (oBal < 0)
+ {
+ a->balance = 0;
+ e->balance = 1;
+ }
+ if (r)
+ {
+ if (f == r->child[RIGHT])
+ return r->RestoreBalances (1, racine);
+ if (f == r->child[LEFT])
+ return r->RestoreBalances (-1, racine);
+ }
+ return avl_no_err;
+ }
+ }
+ }
+ else if (balance == 0)
+ {
+ if (diff < 0)
+ {
+ balance = -1;
+ }
+ else if (diff == 0)
+ {
+ }
+ else if (diff > 0)
+ {
+ balance = 1;
+ }
+ return avl_no_err;
+ }
+ else if (balance < 0)
+ {
+ if (diff < 0)
+ {
+ if (child[RIGHT] == nullptr)
+ {
+// cout << "un probleme\n";
+ return avl_bal_err;
+ }
+ AVLTree *r = parent;
+ AVLTree *a = this;
+ AVLTree *b = child[LEFT];
+ AVLTree *e = child[RIGHT];
+ AVLTree *f = e->child[LEFT];
+ AVLTree *g = e->child[RIGHT];
+ if (e->balance < 0)
+ {
+ e->child[LEFT] = a;
+ e->child[RIGHT] = g;
+ a->child[LEFT] = b;
+ a->child[RIGHT] = f;
+ if (a)
+ a->parent = e;
+ if (g)
+ g->parent = e;
+ if (b)
+ b->parent = a;
+ if (f)
+ f->parent = a;
+ e->parent = r;
+ if (r)
+ {
+ if (r->child[LEFT] == a)
+ r->child[LEFT] = e;
+ if (r->child[RIGHT] == a)
+ r->child[RIGHT] = e;
+ }
+ if (racine == this)
+ racine = e;
+ e->balance = 0;
+ a->balance = 0;
+ if (r)
+ {
+ if (e == r->child[RIGHT])
+ return r->RestoreBalances (1, racine);
+ if (e == r->child[LEFT])
+ return r->RestoreBalances (-1, racine);
+ }
+ return avl_no_err;
+ }
+ else if (e->balance == 0)
+ {
+ e->child[LEFT] = a;
+ e->child[RIGHT] = g;
+ a->child[LEFT] = b;
+ a->child[RIGHT] = f;
+ if (a)
+ a->parent = e;
+ if (g)
+ g->parent = e;
+ if (b)
+ b->parent = a;
+ if (f)
+ f->parent = a;
+ e->parent = r;
+ if (r)
+ {
+ if (r->child[LEFT] == a)
+ r->child[LEFT] = e;
+ if (r->child[RIGHT] == a)
+ r->child[RIGHT] = e;
+ }
+ if (racine == this)
+ racine = e;
+ e->balance = 1;
+ a->balance = -1;
+ return avl_no_err;
+ }
+ else if (e->balance > 0)
+ {
+ if (child[RIGHT]->child[LEFT] == nullptr)
+ {
+// cout << "un probleme\n";
+ return avl_bal_err;
+ }
+ AVLTree *i = child[RIGHT]->child[LEFT]->child[LEFT];
+ AVLTree *j = child[RIGHT]->child[LEFT]->child[RIGHT];
+
+ f->child[LEFT] = a;
+ f->child[RIGHT] = e;
+ a->child[LEFT] = b;
+ a->child[RIGHT] = i;
+ e->child[LEFT] = j;
+ e->child[RIGHT] = g;
+ if (b)
+ b->parent = a;
+ if (i)
+ i->parent = a;
+ if (g)
+ g->parent = e;
+ if (j)
+ j->parent = e;
+ if (a)
+ a->parent = f;
+ if (e)
+ e->parent = f;
+ f->parent = r;
+ if (r)
+ {
+ if (r->child[LEFT] == a)
+ r->child[LEFT] = f;
+ if (r->child[RIGHT] == a)
+ r->child[RIGHT] = f;
+ }
+ if (racine == this)
+ racine = f;
+ int oBal = f->balance;
+ f->balance = 0;
+ if (oBal > 0)
+ {
+ a->balance = 0;
+ e->balance = -1;
+ }
+ else if (oBal == 0)
+ {
+ a->balance = 0;
+ e->balance = 0;
+ }
+ else if (oBal < 0)
+ {
+ a->balance = 1;
+ e->balance = 0;
+ }
+ if (r)
+ {
+ if (f == r->child[RIGHT])
+ return r->RestoreBalances (1, racine);
+ if (f == r->child[LEFT])
+ return r->RestoreBalances (-1, racine);
+ }
+ return avl_no_err;
+ }
+ }
+ else if (diff == 0)
+ {
+ }
+ else if (diff > 0)
+ {
+ balance = 0;
+ if (parent)
+ {
+ if (this == parent->child[RIGHT])
+ return parent->RestoreBalances (1, racine);
+ if (this == parent->child[LEFT])
+ return parent->RestoreBalances (-1, racine);
+ }
+ return avl_no_err;
+ }
+ }
+ return avl_no_err;
+}
+
+/*
+ * removal
+ */
+int
+AVLTree::Remove (AVLTree * &racine, bool rebalance)
+{
+ AVLTree *startNode = nullptr;
+ int remDiff = 0;
+ int res = Remove (racine, startNode, remDiff);
+ if (res == avl_no_err && rebalance && startNode)
+ res = startNode->RestoreBalances (remDiff, racine);
+ return res;
+}
+
+int
+AVLTree::Remove (AVLTree * &racine, AVLTree * &startNode, int &diff)
+{
+ if (elem[LEFT])
+ elem[LEFT]->elem[RIGHT] = elem[RIGHT];
+ if (elem[RIGHT])
+ elem[RIGHT]->elem[LEFT] = elem[LEFT];
+ elem[LEFT] = elem[RIGHT] = nullptr;
+
+ if (child[LEFT] && child[RIGHT])
+ {
+ AVLTree *newMe = child[LEFT]->leafFromParent(this, RIGHT);
+ if (newMe == nullptr || newMe->child[RIGHT])
+ {
+// cout << "pas normal\n";
+ return avl_rm_err;
+ }
+ if (newMe == child[LEFT])
+ {
+ startNode = newMe;
+ diff = -1;
+ newMe->child[RIGHT] = child[RIGHT];
+ child[RIGHT]->parent = newMe;
+ newMe->parent = parent;
+ if (parent)
+ {
+ if (parent->child[LEFT] == this)
+ parent->child[LEFT] = newMe;
+ if (parent->child[RIGHT] == this)
+ parent->child[RIGHT] = newMe;
+ }
+ }
+ else
+ {
+ AVLTree *oParent = newMe->parent;
+ startNode = oParent;
+ diff = 1;
+
+ oParent->child[RIGHT] = newMe->child[LEFT];
+ if (newMe->child[LEFT])
+ newMe->child[LEFT]->parent = oParent;
+
+ newMe->parent = parent;
+ newMe->child[LEFT] = child[LEFT];
+ newMe->child[RIGHT] = child[RIGHT];
+ if (parent)
+ {
+ if (parent->child[LEFT] == this)
+ parent->child[LEFT] = newMe;
+ if (parent->child[RIGHT] == this)
+ parent->child[RIGHT] = newMe;
+ }
+ if (child[LEFT])
+ child[LEFT]->parent = newMe;
+ if (child[RIGHT])
+ child[RIGHT]->parent = newMe;
+ }
+ newMe->balance = balance;
+ if (racine == this)
+ racine = newMe;
+ }
+ else if (child[LEFT])
+ {
+ startNode = parent;
+ diff = 0;
+ if (parent)
+ {
+ if (this == parent->child[LEFT])
+ diff = -1;
+ if (this == parent->child[RIGHT])
+ diff = 1;
+ }
+ if (parent)
+ {
+ if (parent->child[LEFT] == this)
+ parent->child[LEFT] = child[LEFT];
+ if (parent->child[RIGHT] == this)
+ parent->child[RIGHT] = child[LEFT];
+ }
+ if (child[LEFT]->parent == this)
+ child[LEFT]->parent = parent;
+ if (racine == this)
+ racine = child[LEFT];
+ }
+ else if (child[RIGHT])
+ {
+ startNode = parent;
+ diff = 0;
+ if (parent)
+ {
+ if (this == parent->child[LEFT])
+ diff = -1;
+ if (this == parent->child[RIGHT])
+ diff = 1;
+ }
+ if (parent)
+ {
+ if (parent->child[LEFT] == this)
+ parent->child[LEFT] = child[RIGHT];
+ if (parent->child[RIGHT] == this)
+ parent->child[RIGHT] = child[RIGHT];
+ }
+ if (child[RIGHT]->parent == this)
+ child[RIGHT]->parent = parent;
+ if (racine == this)
+ racine = child[RIGHT];
+ }
+ else
+ {
+ startNode = parent;
+ diff = 0;
+ if (parent)
+ {
+ if (this == parent->child[LEFT])
+ diff = -1;
+ if (this == parent->child[RIGHT])
+ diff = 1;
+ }
+ if (parent)
+ {
+ if (parent->child[LEFT] == this)
+ parent->child[LEFT] = nullptr;
+ if (parent->child[RIGHT] == this)
+ parent->child[RIGHT] = nullptr;
+ }
+ if (racine == this)
+ racine = nullptr;
+ }
+ parent = child[RIGHT] = child[LEFT] = nullptr;
+ balance = 0;
+ return avl_no_err;
+}
+
+/*
+ * insertion
+ */
+int
+AVLTree::Insert (AVLTree * &racine, int insertType, AVLTree * insertL,
+ AVLTree * insertR, bool rebalance)
+{
+ int res = Insert (racine, insertType, insertL, insertR);
+ if (res == avl_no_err && rebalance)
+ res = RestoreBalances ((AVLTree *) nullptr, racine);
+ return res;
+}
+
+int
+AVLTree::Insert (AVLTree * &racine, int insertType, AVLTree * insertL,
+ AVLTree * insertR)
+{
+ if (racine == nullptr)
+ {
+ racine = this;
+ return avl_no_err;
+ }
+ else
+ {
+ if (insertType == not_found)
+ {
+// cout << "pb avec l'arbre de raster\n";
+ return avl_ins_err;
+ }
+ else if (insertType == found_on_left)
+ {
+ if (insertR == nullptr || insertR->child[LEFT])
+ {
+// cout << "ngou?\n";
+ return avl_ins_err;
+ }
+ insertR->child[LEFT] = this;
+ parent = insertR;
+ insertOn(LEFT, insertR);
+ }
+ else if (insertType == found_on_right)
+ {
+ if (insertL == nullptr || insertL->child[RIGHT])
+ {
+// cout << "ngou?\n";
+ return avl_ins_err;
+ }
+ insertL->child[RIGHT] = this;
+ parent = insertL;
+ insertOn(RIGHT, insertL);
+ }
+ else if (insertType == found_between)
+ {
+ if (insertR == nullptr || insertL == nullptr
+ || (insertR->child[LEFT] != nullptr && insertL->child[RIGHT] != nullptr))
+ {
+// cout << "ngou?\n";
+ return avl_ins_err;
+ }
+ if (insertR->child[LEFT] == nullptr)
+ {
+ insertR->child[LEFT] = this;
+ parent = insertR;
+ }
+ else if (insertL->child[RIGHT] == nullptr)
+ {
+ insertL->child[RIGHT] = this;
+ parent = insertL;
+ }
+ insertBetween (insertL, insertR);
+ }
+ else if (insertType == found_exact)
+ {
+ if (insertL == nullptr)
+ {
+// cout << "ngou?\n";
+ return avl_ins_err;
+ }
+ // et on insere
+
+ if (insertL->child[RIGHT])
+ {
+ insertL = insertL->child[RIGHT]->leafFromParent(insertL, LEFT);
+ if (insertL->child[LEFT])
+ {
+// cout << "ngou?\n";
+ return avl_ins_err;
+ }
+ insertL->child[LEFT] = this;
+ this->parent = insertL;
+ insertBetween (insertL->elem[LEFT], insertL);
+ }
+ else
+ {
+ insertL->child[RIGHT] = this;
+ parent = insertL;
+ insertBetween (insertL, insertL->elem[RIGHT]);
+ }
+ }
+ else
+ {
+ // cout << "code incorrect\n";
+ return avl_ins_err;
+ }
+ }
+ return avl_no_err;
+}
+
+void
+AVLTree::Relocate (AVLTree * to)
+{
+ if (elem[LEFT])
+ elem[LEFT]->elem[RIGHT] = to;
+ if (elem[RIGHT])
+ elem[RIGHT]->elem[LEFT] = to;
+ to->elem[LEFT] = elem[LEFT];
+ to->elem[RIGHT] = elem[RIGHT];
+
+ if (parent)
+ {
+ if (parent->child[LEFT] == this)
+ parent->child[LEFT] = to;
+ if (parent->child[RIGHT] == this)
+ parent->child[RIGHT] = to;
+ }
+ if (child[RIGHT])
+ {
+ child[RIGHT]->parent = to;
+ }
+ if (child[LEFT])
+ {
+ child[LEFT]->parent = to;
+ }
+ to->parent = parent;
+ to->child[RIGHT] = child[RIGHT];
+ to->child[LEFT] = child[LEFT];
+}
+
+
+void AVLTree::insertOn(Side s, AVLTree *of)
+{
+ elem[1 - s] = of;
+ if (of)
+ of->elem[s] = this;
+}
+
+void AVLTree::insertBetween(AVLTree *l, AVLTree *r)
+{
+ if (l)
+ l->elem[RIGHT] = this;
+ if (r)
+ r->elem[LEFT] = this;
+ elem[LEFT] = l;
+ elem[RIGHT] = r;
+}
+
+/*
+ Local Variables:
+ mode:c++
+ c-file-style:"stroustrup"
+ c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+ indent-tabs-mode:nil
+ fill-column:99
+ End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :