Tree.h

/*
 *  stree::Tree class interface
 *
 *  This file is part of OTAWA
 *  Copyright (c) 2013, IRIT UPS.
 *
 *  OTAWA is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  OTAWA 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with OTAWA; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#ifndef ELM_STREE_TREE_H_
#define ELM_STREE_TREE_H_

#include <elm/compare.h>
#include <elm/genstruct/AVLTree.h>

namespace elm { namespace stree {

// Tree class
template <class K, class T, class C = Comparator<K> >
class Tree {
    static const int null = -1;

public:
    typedef struct node_t {
        inline node_t(void) { }
        inline node_t(struct node_t s[], int _ll, int _rl)
            : lb(s[_ll].lb), ub(s[_rl].ub), ll(_ll), rl(_rl) { }
        inline node_t(const K& _lb, const K& _ub)
            : lb(_lb), ub(_ub), ll(null), rl(null) { }
        inline bool isLeaf(void) const { return ll == null; }
        inline int left(void) const { return ll; }
        inline int right(void) const { return rl; }
        inline const K& lowerBound(void) const { return lb; }
        inline const K& upperBound(void) const { return ub; }
        K lb, ub;
        int ll, rl;
        T data;
    } node_t;

    inline Tree(void): root(-1), nodes(0) { }
    inline Tree(int _root, node_t *_nodes): root(_root), nodes(_nodes) { }
    inline void set(int _root, node_t *_nodes) { root = _root; nodes = _nodes; }

    ~Tree(void) { delete [] nodes; }

    inline const T& get(const K& key, const T& def) const
        { T *val = find(key); if(!val) return def; else return *val; }
    inline const T& get(const K& key) const
        { T *val = find(key); ASSERTP(val, "out of tree"); return *val; }
    inline T& get(const K& key)
        { T *val = find(key); ASSERTP(val, "out of tree"); return *val; }
    inline bool contains(const K& key) const
        { return C::compare(key, nodes[root].lowerBound()) >= 0 && C::compare(key, nodes[root].upperBound()) <= 0; }

#   ifdef ELM_STREE_DEBUG
        void dump(io::Output& out = cout, int i = -1, int t = 0) {
            if(i < 0) i = root;
            for(int j = 0; j < t; j++) out << "| ";
            out << "|- ";
            out << nodes[i].lowerBound() << " - " << nodes[i].upperBound();
            if(nodes[i].isLeaf())
                out << " -> " << nodes[i].data << io::endl;
            else {
                out << io::endl;
                dump(out, nodes[i].left(), t + 1);
                dump(out, nodes[i].right(), t + 1);
            }
        }
#   endif

protected:
    T *find(const K& key) const {
        ASSERTP(nodes && root >= 0, "uninitialized stree");
        int i = root;
        if(!contains(key))
            return 0;
        while(!nodes[i].isLeaf()) {
            if(C::compare(key, nodes[nodes[i].right()].lowerBound()) < 0)
                i = nodes[i].left();
            else
                i = nodes[i].right();
        }
        return &nodes[i].data;
    }

private:
    int root;
    node_t *nodes;
};

} } // elm::stree

#endif /* ELM_STREE_TREE_H_ */