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-rw-r--r--gnu/lib/libg++/g++-include/XPPQ.ccP143
1 files changed, 143 insertions, 0 deletions
diff --git a/gnu/lib/libg++/g++-include/XPPQ.ccP b/gnu/lib/libg++/g++-include/XPPQ.ccP
new file mode 100644
index 000000000000..41515a39bbbf
--- /dev/null
+++ b/gnu/lib/libg++/g++-include/XPPQ.ccP
@@ -0,0 +1,143 @@
+// 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 "<T>.XPPQ.h"
+
+int <T>XPPQ::OK()
+{
+ int v = p.OK();
+ v &= p.low() == 1;
+ v &= count == p.length();
+ if (!v) error("invariant failure");
+ return v;
+}
+
+Pix <T>XPPQ::seek(<T&> item)
+{
+ for (int i = p.low(); i < p.fence(); p.next(i))
+ if (<T>EQ(p[i],item)) return p.index_to_Pix(i);
+ return 0;
+}
+
+// standard 2-ary heap ops
+// pointers are used a lot to avoid thrashing across chunks with plexes
+
+Pix <T>XPPQ::enq(<T&> item)
+{
+ p.add_high(item);
+ <T>* pk = &(p.high_element());
+ int par = ++count >> 1;
+ while (par != 0)
+ {
+ <T>* ppar = &(p[par]);
+ if (!(<T>LE(*ppar, item)))
+ {
+ *pk = *ppar;
+ pk = ppar;
+ par >>= 1;
+ }
+ else
+ break;
+ }
+ *pk = item;
+ return Pix(pk);
+}
+
+void <T>XPPQ::del_front()
+{
+ if (count == 0) error("empty PQ");
+ --count;
+ <T>* pk = &(p.low_element());
+ <T>* ph = &(p.high_element());
+ int child = 2;
+ while (child <= count)
+ {
+ <T>* pchild = &(p[child]);
+ if (child < count)
+ {
+ <T>* prchild = &(p[child+1]);
+ if (!(<T>LE(*pchild, *prchild)))
+ {
+ pchild = prchild;
+ ++child;
+ }
+ }
+ if (!(<T>LE(*ph, *pchild)))
+ {
+ *pk = *pchild;
+ pk = pchild;
+ child <<= 1;
+ }
+ else
+ break;
+ }
+ *pk = *ph;
+ p.del_high();
+}
+
+
+void <T>XPPQ::del(Pix i)
+{
+ if (i == 0) error("null Pix");
+ --count;
+ int k = p.Pix_to_index(i);
+ <T>* pk = &(p[k]);
+ <T>* ph = &(p.high_element());
+ int child = k << 1;
+ while (child <= count)
+ {
+ <T>* pchild = &(p[child]);
+ if (child < count)
+ {
+ <T>* prchild = &(p[child+1]);
+ if (!(<T>LE(*pchild, *prchild)))
+ {
+ pchild = prchild;
+ ++child;
+ }
+ }
+ if (!(<T>LE(*ph, *pchild)))
+ {
+ *pk = *pchild;
+ pk = pchild;
+ child <<= 1;
+ }
+ else
+ break;
+ }
+ int par = child >> 2;
+ while (par != 0)
+ {
+ <T>* ppar = &(p[par]);
+ if (!(<T>LE(*ppar, *ph)))
+ {
+ *pk = *ppar;
+ pk = ppar;
+ par >>= 1;
+ }
+ else
+ break;
+ }
+ *pk = *ph;
+ p.del_high();
+}
+
+