libcds/src/static_sequence/wt_node_internal.cpp

   1 /* wt_node_internal.cpp
   2  * Copyright (C) 2008, Francisco Claude, all rights reserved.
   3  *
   4  * wt_node_internal
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  *
  20  */
  21
  22 #include <wt_node_internal.h>
  23
  24 wt_node_internal::wt_node_internal(uint * symbols, uint n, uint l, wt_coder * c, static_bitsequence_builder * bmb) {
  25         uint * ibitmap = new uint[n/W+1];
  26         for(uint i=0;i<n/W+1;i++)
  27                 ibitmap[i]=0;
  28         for(uint i=0;i<n;i++)
  29                 if(c->is_set(symbols[i],l))
  30                         bitset(ibitmap,i);
  31         bitmap = bmb->build(ibitmap, n);
  32   delete [] ibitmap;
  33         uint count_right = bitmap->rank1(n-1);
  34         uint count_left = n-count_right+1;
  35         uint * left = new uint[count_left+1];
  36         uint * right = new uint[count_right+1];
  37         count_right = count_left = 0;
  38         bool match_left = true, match_right = true;
  39         for(uint i=0;i<n;i++) {
  40                 if(bitmap->access(i)) {
  41                         right[count_right++]=symbols[i];
  42                         if(count_right>1)
  43                                 if(right[count_right-1]!=right[count_right-2])
  44                                         match_right = false;
  45                 }
  46                 else {
  47                         left[count_left++]=symbols[i];
  48                         if(count_left>1)
  49                                 if(left[count_left-1]!=left[count_left-2])
  50                                         match_left = false;
  51                 }
  52         }
  53         if(count_left>0) {
  54                 if(match_left/* && c->done(left[0],l+1)*/)
  55                         left_child = new wt_node_leaf(left[0], count_left);
  56                 else
  57                         left_child = new wt_node_internal(left, count_left, l+1, c, bmb);
  58         } else {
  59                 left_child = NULL;
  60         }
  61         if(count_right>0) {
  62                 if(match_right/* && c->done(right[0],l+1)*/)
  63                         right_child = new wt_node_leaf(right[0], count_right);
  64                 else
  65                         right_child = new wt_node_internal(right, count_right, l+1, c, bmb);
  66         } else {
  67                 right_child = NULL;
  68         }
  69         delete [] left;
  70         delete [] right;
  71 }
  72
  73 wt_node_internal::wt_node_internal(uchar * symbols, uint n, uint l, wt_coder * c, static_bitsequence_builder * bmb) {
  74         uint * ibitmap = new uint[n/W+1];
  75         for(uint i=0;i<n/W+1;i++)
  76                 ibitmap[i]=0;
  77         for(uint i=0;i<n;i++)
  78                 if(c->is_set((uint)symbols[i],l))
  79                         bitset(ibitmap,i);
  80         bitmap = bmb->build(ibitmap, n);
  81   delete [] ibitmap;
  82         uint count_right = bitmap->rank1(n-1);
  83         uint count_left = n-count_right+1;
  84         uchar * left = new uchar[count_left+1];
  85         uchar * right = new uchar[count_right+1];
  86         count_right = count_left = 0;
  87         bool match_left = true, match_right = true;
  88         for(uint i=0;i<n;i++) {
  89                 if(bitmap->access(i)) {
  90                         right[count_right++]=symbols[i];
  91                         if(count_right>1)
  92                                 if(right[count_right-1]!=right[count_right-2])
  93                                         match_right = false;
  94                 }
  95                 else {
  96                         left[count_left++]=symbols[i];
  97                         if(count_left>1)
  98                                 if(left[count_left-1]!=left[count_left-2])
  99                                         match_left = false;
 100                 }
 101         }
 102         if(count_left>0) {
 103                 if(match_left/* && c->done(left[0],l+1)*/)
 104                         left_child = new wt_node_leaf((uint)left[0], count_left);
 105                 else
 106                         left_child = new wt_node_internal(left, count_left, l+1, c, bmb);
 107         } else {
 108                 left_child = NULL;
 109         }
 110         if(count_right>0) {
 111                 if(match_right/* && c->done(right[0],l+1)*/)
 112                         right_child = new wt_node_leaf((uint)right[0], count_right);
 113                 else
 114                         right_child = new wt_node_internal(right, count_right, l+1, c, bmb);
 115         } else {
 116                 right_child = NULL;
 117         }
 118         delete [] left;
 119         delete [] right;
 120 }
 121
 122
 123 wt_node_internal::wt_node_internal() { }
 124
 125 wt_node_internal::~wt_node_internal() {
 126         delete bitmap;
 127         if(right_child!=NULL) delete right_child;
 128         if(left_child!=NULL) delete left_child;
 129 }
 130
 131 uint wt_node_internal::rank(uint symbol, uint pos, uint l, wt_coder * c) {
 132         bool is_set = c->is_set(symbol,l);
 133         if(!is_set) {
 134                 if(left_child==NULL) return 0;
 135                 return left_child->rank(symbol, bitmap->rank0(pos)-1,l+1,c);
 136         }
 137         else {
 138                 if(right_child==NULL) return 0;
 139                 return right_child->rank(symbol, bitmap->rank1(pos)-1,l+1,c);
 140         }
 141 }
 142
 143 uint wt_node_internal::select(uint symbol, uint pos, uint l, wt_coder * c) {
 144         bool is_set = c->is_set(symbol, l);
 145         uint ret = 0;
 146         if(!is_set) {
 147                 if(left_child==NULL)
 148                         return (uint)(-1);
 149                 uint new_pos = left_child->select(symbol, pos, l+1,c);
 150                 if(new_pos+1==0) return (uint)(-1);
 151                 ret = bitmap->select0(new_pos)+1;
 152         } else {
 153                 if(right_child==NULL)
 154                         return (uint)(-1);
 155                 uint new_pos = right_child->select(symbol, pos, l+1,c);
 156                 if(new_pos+1==0) return (uint)(-1);
 157                 ret = bitmap->select1(new_pos)+1;
 158         }
 159         if(ret==0) return (uint)-1;
 160         return ret;
 161 }
 162
 163 uint wt_node_internal::access(uint pos) {
 164         bool is_set = bitmap->access(pos);
 165         if(!is_set) {
 166                 assert(left_child!=NULL);
 167                 return left_child->access(bitmap->rank0(pos)-1);
 168         } else {
 169                 assert(right_child!=NULL);
 170                 return right_child->access(bitmap->rank1(pos)-1);
 171         }
 172 }
 173
 174 uint wt_node_internal::size() {
 175         uint s = bitmap->size()+sizeof(wt_node_internal);
 176         if(left_child!=NULL)
 177                 s += left_child->size();
 178         if(right_child!=NULL)
 179                 s += right_child->size();
 180         return s;
 181 }
 182
 183 uint wt_node_internal::save(FILE *fp) {
 184   uint wr = WT_NODE_INTERNAL_HDR;
 185   wr = fwrite(&wr,sizeof(uint),1,fp);
 186   if(wr!=1) return 1;
 187   if(bitmap->save(fp)) return 1;
 188   if(left_child!=NULL) {
 189     if(left_child->save(fp)) return 1;
 190   } else {
 191     wr = WT_NODE_NULL_HDR;
 192     wr = fwrite(&wr,sizeof(uint),1,fp);
 193     if(wr!=1) return 1;
 194   }
 195   if(right_child!=NULL) {
 196     if(right_child->save(fp)) return 1;
 197   } else {
 198     wr = WT_NODE_NULL_HDR;
 199     wr = fwrite(&wr,sizeof(uint),1,fp);
 200     if(wr!=1) return 1;
 201   }
 202   return 0;
 203 }
 204
 205 wt_node_internal * wt_node_internal::load(FILE *fp) {
 206   uint rd;
 207   if(fread(&rd,sizeof(uint),1,fp)!=1) return NULL;
 208   if(rd!=WT_NODE_INTERNAL_HDR) return NULL;
 209   wt_node_internal * ret = new wt_node_internal();
 210   ret->bitmap = static_bitsequence::load(fp);
 211   ret->left_child = wt_node::load(fp);
 212   ret->right_child = wt_node::load(fp);
 213   return ret;
 214 }