C++ Tutorial/STL Algorithms Merge/includes

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Container includes: generic includes algorithm

<source lang="cpp">#include <iostream>

  1. include <cassert>
  2. include <algorithm>
  3. include <vector>

using namespace std; int main() {

 bool result;
 string s("abcde");
 string s2("aeiou");
 vector<char> vector1(s.begin(), s.end());
 vector<char> vector2(s2.begin(), s2.end());
 // Illustrate includes:
 result = includes(vector1.begin(), vector1.end(),vector2.begin(), vector2.end());
 assert (result == false);
 result = includes(vector1.begin(), vector1.end(),vector2.begin(), vector2.begin() + 2);
 // "a" and "e" are contained in vector1
 assert (result == true);
 return 0;

}</source>

Determine whether one set is completely contained in another set

<source lang="cpp">#include <iostream> using std::cout; using std::endl;

  1. include <algorithm>
  2. include <iterator>

int main() {

  const int SIZE1 = 10, SIZE2 = 5, SIZE3 = 20;
  int a1[ SIZE1 ] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
  int a2[ SIZE2 ] = { 4, 5, 6, 7, 8 };
  int a3[ SIZE2 ] = { 4, 5, 6, 11, 15 };
  std::ostream_iterator< int > output( cout, " " );
  std::copy( a1, a1 + SIZE1, output );
  cout << "\n";
  std::copy( a2, a2 + SIZE2, output );
  cout << "\n";
  std::copy( a3, a3 + SIZE2, output );
  if ( std::includes( a1, a1 + SIZE1, a2, a2 + SIZE2 ) )
     cout << "\n\na1 includes a2";
  else
     cout << "\n\na1 does not include a2";
  return 0;

}</source>

1 2 3 4 5 6 7 8 9 10
4 5 6 7 8
4 5 6 11 15
a1 includes a2

Use includes and search to check whether all elements in search are also in coll

<source lang="cpp">/* The following code example is taken from the book

* "The C++ Standard Library - A Tutorial and Reference"
* by Nicolai M. Josuttis, Addison-Wesley, 1999
*
* (C) Copyright Nicolai M. Josuttis 1999.
* Permission to copy, use, modify, sell and distribute this software
* is granted provided this copyright notice appears in all copies.
* This software is provided "as is" without express or implied
* warranty, and with no claim as to its suitability for any purpose.
*/
  1. include <iostream>
  2. include <vector>
  3. include <deque>
  4. include <list>
  5. include <set>
  6. include <map>
  7. include <string>
  8. include <algorithm>
  9. include <iterator>
  10. include <functional>
  11. include <numeric>

/* PRINT_ELEMENTS()

* - prints optional C-string optcstr followed by
* - all elements of the collection coll
* - separated by spaces
*/

template <class T> inline void PRINT_ELEMENTS (const T& coll, const char* optcstr="") {

   typename T::const_iterator pos;
   std::cout << optcstr;
   for (pos=coll.begin(); pos!=coll.end(); ++pos) {
       std::cout << *pos << " ";
   }
   std::cout << std::endl;

} /* INSERT_ELEMENTS (collection, first, last)

* - fill values from first to last into the collection
* - NOTE: NO half-open range
*/

template <class T> inline void INSERT_ELEMENTS (T& coll, int first, int last) {

   for (int i=first; i<=last; ++i) {
       coll.insert(coll.end(),i);
   }

} using namespace std; int main() {

   list<int> coll;
   vector<int> search;
   INSERT_ELEMENTS(coll,1,9);
   PRINT_ELEMENTS(coll,"coll:   ");
   search.push_back(3);
   search.push_back(4);
   search.push_back(7);
   PRINT_ELEMENTS(search,"search: ");
   // check whether all elements in search are also in coll
   if (includes (coll.begin(), coll.end(),
                 search.begin(), search.end())) {
       cout << "all elements of search are also in coll"
            << endl;
   }
   else {
       cout << "not all elements of search are also in coll"
            << endl;
   }

}</source>

coll:   1 2 3 4 5 6 7 8 9
search: 3 4 7
all elements of search are also in coll