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-rw-r--r--gnu/lib/libg++/g++-include/SplaySet.ccP499
1 files changed, 499 insertions, 0 deletions
diff --git a/gnu/lib/libg++/g++-include/SplaySet.ccP b/gnu/lib/libg++/g++-include/SplaySet.ccP
new file mode 100644
index 000000000000..bba5601c7eb6
--- /dev/null
+++ b/gnu/lib/libg++/g++-include/SplaySet.ccP
@@ -0,0 +1,499 @@
+// This may look like C code, but it is really -*- C++ -*-
+/*
+Copyright (C) 1988 Free Software Foundation
+ written by Doug Lea (dl@rocky.oswego.edu)
+
+This file is part of the GNU C++ Library. This library is free
+software; you can redistribute it and/or modify it under the terms of
+the GNU Library General Public License as published by the Free
+Software Foundation; either version 2 of the License, or (at your
+option) any later version. This library is distributed in the hope
+that it will be useful, but WITHOUT ANY WARRANTY; without even the
+implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+PURPOSE. See the GNU Library General Public License for more details.
+You should have received a copy of the GNU Library General Public
+License along with this library; if not, write to the Free Software
+Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#ifdef __GNUG__
+#pragma implementation
+#endif
+#include <stream.h>
+#include "<T>.SplaySet.h"
+
+
+/*
+
+ struct to simulate the special `null' node in the Sleater & Tarjan JACM 1985
+ splay tree algorithms
+
+ All routines use a version of their `simple top-down' splay alg. (p 669)
+
+*/
+
+struct _dummySplayNode
+{
+ <T>SplayNode* lt;
+ <T>SplayNode* rt;
+ <T>SplayNode* par;
+} _dummy_null;
+
+
+/*
+ traversal primitives
+*/
+
+
+<T>SplayNode* <T>SplaySet::leftmost()
+{
+ <T>SplayNode* t = root;
+ if (t != 0) while (t->lt != 0) t = t->lt;
+ return t;
+}
+
+<T>SplayNode* <T>SplaySet::rightmost()
+{
+ <T>SplayNode* t = root;
+ if (t != 0) while (t->rt != 0) t = t->rt;
+ return t;
+}
+
+<T>SplayNode* <T>SplaySet::succ(<T>SplayNode* t)
+{
+ if (t == 0)
+ return 0;
+ if (t->rt != 0)
+ {
+ t = t->rt;
+ while (t->lt != 0) t = t->lt;
+ return t;
+ }
+ else
+ {
+ for (;;)
+ {
+ if (t->par == 0 || t == t->par->lt)
+ return t->par;
+ else
+ t = t->par;
+ }
+ }
+}
+
+<T>SplayNode* <T>SplaySet::pred(<T>SplayNode* t)
+{
+ if (t == 0)
+ return 0;
+ else if (t->lt != 0)
+ {
+ t = t->lt;
+ while (t->rt != 0) t = t->rt;
+ return t;
+ }
+ else
+ {
+ for (;;)
+ {
+ if (t->par == 0 || t == t->par->rt)
+ return t->par;
+ else
+ t = t->par;
+ }
+ }
+}
+
+
+Pix <T>SplaySet::seek(<T&> key)
+{
+ <T>SplayNode* t = root;
+ if (t == 0)
+ return 0;
+
+ int comp = <T>CMP(key, t->item);
+ if (comp == 0)
+ return Pix(t);
+
+ <T>SplayNode* dummy = (<T>SplayNode*)(&_dummy_null);
+ <T>SplayNode* l = dummy;
+ <T>SplayNode* r = dummy;
+ dummy->rt = dummy->lt = dummy->par = 0;
+
+ while (comp != 0)
+ {
+ if (comp > 0)
+ {
+ <T>SplayNode* tr = t->rt;
+ if (tr == 0)
+ break;
+ else
+ {
+ comp = <T>CMP(key, tr->item);
+ if (comp <= 0 || tr->rt == 0)
+ {
+ l->rt = t; t->par = l;
+ l = t;
+ t = tr;
+ if (comp >= 0)
+ break;
+ }
+ else
+ {
+ if ((t->rt = tr->lt) != 0) t->rt->par = t;
+ tr->lt = t; t->par = tr;
+ l->rt = tr; tr->par = l;
+ l = tr;
+ t = tr->rt;
+ comp = <T>CMP(key, t->item);
+ }
+ }
+ }
+ else
+ {
+ <T>SplayNode* tl = t->lt;
+ if (tl == 0)
+ break;
+ else
+ {
+ comp = <T>CMP(key, tl->item);
+ if (comp >= 0 || tl->lt == 0)
+ {
+ r->lt = t; t->par = r;
+ r = t;
+ t = tl;
+ if (comp <= 0)
+ break;
+ }
+ else
+ {
+ if ((t->lt = tl->rt) != 0) t->lt->par = t;
+ tl->rt = t; t->par = tl;
+ r->lt = tl; tl->par = r;
+ r = tl;
+ t = tl->lt;
+ comp = <T>CMP(key, t->item);
+ }
+ }
+ }
+ }
+ if ((r->lt = t->rt) != 0) r->lt->par = r;
+ if ((l->rt = t->lt) != 0) l->rt->par = l;
+ if ((t->lt = dummy->rt) != 0) t->lt->par = t;
+ if ((t->rt = dummy->lt) != 0) t->rt->par = t;
+ t->par = 0;
+ root = t;
+ return (comp == 0) ? Pix(t) : 0;
+}
+
+
+
+Pix <T>SplaySet::add(<T&> item)
+{
+ <T>SplayNode* t = root;
+ if (t == 0)
+ {
+ ++count;
+ root = new <T>SplayNode(item);
+ return Pix(root);
+ }
+ int comp = <T>CMP(item, t->item);
+ if (comp == 0)
+ return Pix(t);
+
+ <T>SplayNode* dummy = (<T>SplayNode*)(&_dummy_null);
+ <T>SplayNode* l = dummy;
+ <T>SplayNode* r = dummy;
+ dummy->rt = dummy->lt = dummy->par = 0;
+
+ while (comp != 0)
+ {
+ if (comp > 0)
+ {
+ <T>SplayNode* tr = t->rt;
+ if (tr == 0)
+ {
+ ++count;
+ tr = new <T>SplayNode(item);
+ comp = 0;
+ }
+ else
+ comp = <T>CMP(item, tr->item);
+
+ if (comp <= 0)
+ {
+ l->rt = t; t->par = l;
+ l = t;
+ t = tr;
+ }
+ else
+ {
+ <T>SplayNode* trr = tr->rt;
+ if (trr == 0)
+ {
+ ++count;
+ trr = new <T>SplayNode(item);
+ comp = 0;
+ }
+ else
+ comp = <T>CMP(item, trr->item);
+
+ if ((t->rt = tr->lt) != 0) t->rt->par = t;
+ tr->lt = t; t->par = tr;
+ l->rt = tr; tr->par = l;
+ l = tr;
+ t = trr;
+ }
+ }
+ else
+ {
+ <T>SplayNode* tl = t->lt;
+ if (tl == 0)
+ {
+ ++count;
+ tl = new <T>SplayNode(item);
+ comp = 0;
+ }
+ else
+ comp = <T>CMP(item, tl->item);
+
+ if (comp >= 0)
+ {
+ r->lt = t; t->par = r;
+ r = t;
+ t = tl;
+ }
+ else
+ {
+ <T>SplayNode* tll = tl->lt;
+ if (tll == 0)
+ {
+ ++count;
+ tll = new <T>SplayNode(item);
+ comp = 0;
+ }
+ else
+ comp = <T>CMP(item, tll->item);
+
+ if ((t->lt = tl->rt) != 0) t->lt->par = t;
+ tl->rt = t; t->par = tl;
+ r->lt = tl; tl->par = r;
+ r = tl;
+ t = tll;
+ }
+ }
+ }
+ if ((r->lt = t->rt) != 0) r->lt->par = r;
+ if ((l->rt = t->lt) != 0) l->rt->par = l;
+ if ((t->lt = dummy->rt) != 0) t->lt->par = t;
+ if ((t->rt = dummy->lt) != 0) t->rt->par = t;
+ t->par = 0;
+ root = t;
+ return Pix(root);
+}
+
+void <T>SplaySet::del(<T&> key)
+{
+ <T>SplayNode* t = (<T>SplayNode*)(seek(key));
+ if (t == 0) return;
+
+ <T>SplayNode* p = t->par;
+
+ --count;
+ if (t->rt == 0)
+ {
+ if (t == root)
+ {
+ if ((root = t->lt) != 0) root->par = 0;
+ }
+ else if (t == p->lt)
+ {
+ if ((p->lt = t->lt) != 0) p->lt->par = p;
+ }
+ else
+ if ((p->rt = t->lt) != 0) p->rt->par = p;
+ }
+ else
+ {
+ <T>SplayNode* r = t->rt;
+ <T>SplayNode* l = r->lt;
+ for(;;)
+ {
+ if (l == 0)
+ {
+ if (t == root)
+ {
+ root = r;
+ r->par = 0;
+ }
+ else if (t == p->lt)
+ {
+ p->lt = r;
+ r->par = p;
+ }
+ else
+ {
+ p->rt = r;
+ r->par = p;
+ }
+ if ((r->lt = t->lt) != 0) r->lt->par = r;
+ break;
+ }
+ else
+ {
+ if ((r->lt = l->rt) != 0) r->lt->par = r;
+ l->rt = r; r->par = l;
+ r = l;
+ l = l->lt;
+ }
+ }
+ }
+ delete t;
+}
+
+
+void <T>SplaySet::_kill(<T>SplayNode* t)
+{
+ if (t != 0)
+ {
+ _kill(t->lt);
+ _kill(t->rt);
+ delete t;
+ }
+}
+
+
+<T>SplayNode* <T>SplaySet::_copy(<T>SplayNode* t)
+{
+ if (t != 0)
+ {
+ <T>SplayNode* l = _copy(t->lt);
+ <T>SplayNode* r = _copy(t->rt);
+ <T>SplayNode* x = new <T>SplayNode(t->item, l, r);
+ if (l != 0) l->par = x;
+ if (r != 0) r->par = x;
+ return x;
+ }
+ else
+ return 0;
+}
+
+/* relationals */
+
+int <T>SplaySet::operator == (<T>SplaySet& y)
+{
+ if (count != y.count)
+ return 0;
+ else
+ {
+ <T>SplayNode* t = leftmost();
+ <T>SplayNode* u = y.leftmost();
+ for (;;)
+ {
+ if (t == 0)
+ return 1;
+ else if (!<T>EQ(t->item, u->item))
+ return 0;
+ else
+ {
+ t = succ(t);
+ u = y.succ(u);
+ }
+ }
+ }
+}
+
+int <T>SplaySet::operator <= (<T>SplaySet& y)
+{
+ if (count > y.count)
+ return 0;
+ else
+ {
+ <T>SplayNode* t = leftmost();
+ <T>SplayNode* u = y.leftmost();
+ for (;;)
+ {
+ if (t == 0)
+ return 1;
+ else if (u == 0)
+ return 0;
+ int cmp = <T>CMP(t->item, u->item);
+ if (cmp == 0)
+ {
+ t = succ(t);
+ u = y.succ(u);
+ }
+ else if (cmp < 0)
+ return 0;
+ else
+ u = y.succ(u);
+ }
+ }
+}
+
+
+void <T>SplaySet::operator |=(<T>SplaySet& y)
+{
+ if (&y == this) return;
+ <T>SplayNode* u = y.leftmost();
+ while (u != 0)
+ {
+ add(u->item);
+ u = y.succ(u);
+ }
+}
+
+void <T>SplaySet::operator &= (<T>SplaySet& y)
+{
+ if (y.count == 0)
+ clear();
+ else if (&y != this && count != 0)
+ {
+ <T>SplayNode* t = leftmost();
+ while (t != 0)
+ {
+ <T>SplayNode* s = succ(t);
+ if (y.seek(t->item) == 0) del(t->item);
+ t = s;
+ }
+ }
+}
+
+
+void <T>SplaySet::operator -=(<T>SplaySet& y)
+{
+ if (&y == this)
+ clear();
+ else if (y.count != 0)
+ {
+ <T>SplayNode* t = leftmost();
+ while (t != 0)
+ {
+ <T>SplayNode* s = succ(t);
+ if (y.seek(t->item) != 0) del(t->item);
+ t = s;
+ }
+ }
+}
+
+int <T>SplaySet::OK()
+{
+ int v = 1;
+ if (root == 0)
+ v = count == 0;
+ else
+ {
+ int n = 1;
+ <T>SplayNode* trail = leftmost();
+ <T>SplayNode* t = succ(trail);
+ while (t != 0)
+ {
+ ++n;
+ v &= <T>CMP(trail->item, t->item) < 0;
+ trail = t;
+ t = succ(t);
+ }
+ v &= n == count;
+ }
+ if (!v) error("invariant failure");
+ return v;
+}
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