libstdc++-v3/testsuite/ext/pb_ds/example/trie_dna.cc

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005, 2006 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
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   7 // of the GNU General Public License as published by the Free Software
   8 // Foundation; either version 2, or (at your option) any later
   9 // version.
  10
  11 // This library is distributed in the hope that it will be useful, but
  12 // WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 // General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License
  17 // along with this library; see the file COPYING.  If not, write to
  18 // the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
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  21 // As a special exception, you may use this file as part of a free
  22 // software library without restriction.  Specifically, if other files
  23 // instantiate templates or use macros or inline functions from this
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  25 // produce an executable, this file does not by itself cause the
  26 // resulting executable to be covered by the GNU General Public
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  28 // reasons why the executable file might be covered by the GNU General
  29 // Public License.
  30
  31 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
  32
  33 // Permission to use, copy, modify, sell, and distribute this software
  34 // is hereby granted without fee, provided that the above copyright
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  40 // warranty.
  41
  42 /**
  43  * @file trie_dna_example.cpp
  44  * An example showing how to use a trie for storing DNA strings.
  45  */
  46
  47 /**
  48  * This example shows how to use a PATRICIA trie for storing
  49  DNA strings. The main point is writing element-access traits
  50  for these strings.
  51 */
  52
  53 #include <cassert>
  54 #include <iostream>
  55 #include <ext/pb_ds/assoc_container.hpp>
  56 #include <ext/pb_ds/trie_policy.hpp>
  57
  58 using namespace std;
  59 using namespace pb_ds;
  60
  61 // DNA is represented by a string.
  62 typedef string dna_t;
  63
  64 // Following is an element access traits for a DNA string.
  65 struct dna_string_e_access_traits
  66 {
  67 public:
  68   typedef size_t size_type;
  69   typedef dna_t key_type;
  70   typedef const key_type& const_key_reference;
  71   typedef char e_type;
  72   typedef string::const_iterator const_iterator;
  73
  74   enum
  75     {
  76       // Number of distinct elements. This is 4 = |{'A', 'C', 'G', 'T'}|
  77       max_size = 4
  78     };
  79
  80   // Returns a const_iterator to the firstelement of r_key.
  81   inline static const_iterator
  82   begin(const_key_reference r_key)
  83   { return r_key.begin(); }
  84
  85   // Returns a const_iterator to the after-lastelement of r_key.
  86   inline static const_iterator
  87   end(const_key_reference r_key)
  88   { return r_key.end(); }
  89
  90   // Maps an element to a position.
  91   inline static size_t
  92   e_pos(e_type e)
  93   {
  94     switch(e)
  95       {
  96       case 'A':
  97         return 0;
  98       case 'C':
  99         return 1;
 100       case 'G':
 101         return 2;
 102       case 'T':
 103         return 3;
 104       default:
 105         abort();
 106       };
 107   }
 108 };
 109
 110 // A PATRICIA trie with DNA string element-access traits.
 111 typedef dna_string_e_access_traits traits_type;
 112 typedef trie<dna_t, string, traits_type> trie_type;
 113
 114 int main()
 115 {
 116   trie_type t;
 117
 118   // Now map some DNAs to diseases in namespace STD.
 119   t["ACCGGTTACTGGTA"] = "gonorrhea";
 120   t["CCGTTATCGGTA"] = "syphlis";
 121
 122   // Check gonorrhea already contracted.
 123   assert(t.find("ACCGGTTACTGGTA") != t.end());
 124
 125   return 0;
 126 }
 127