C++/STL Algorithms Merge/includes

Container includes: generic includes algorithm

<source lang="cpp">

1. include <iostream>
2. include <cassert>
3. include <algorithm>
4. 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">

1. 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;

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

*/        
   
 </source>

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;
   }

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

*/
       
   
 </source>

Use includes() function to check if one set contains another set

<source lang="cpp">

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

using namespace std;

void print(int elem) {

 cout << elem << " ";

} int main(int argc, char** argv) {

 vector<int> setOne, setTwo, setThree;
 setOne.push_back(1);
 setOne.push_back(2);
 setOne.push_back(3);
 
 setTwo.push_back(2);
 setTwo.push_back(3);
 setTwo.push_back(4);
 // set algorithms work on sorted ranges
 sort(setOne.begin(), setOne.end());
 sort(setTwo.begin(), setTwo.end());
 if (includes(setOne.begin(), setOne.end(), setTwo.begin(), setTwo.end())) {
   cout << "The second set is a subset of the first\n";
 }
 if (includes(setTwo.begin(), setTwo.end(), setOne.begin(), setOne.end())) {
   cout << "The first set is a subset of the second\n";
 }
 return (0);

}

 </source>

Use includes() to check for subset

<source lang="cpp">

1. include <iostream>
2. include <list>
3. include <algorithm>

using namespace std; template<class InIter> void show_range(const char *msg, InIter start, InIter end); int main() {

 list<char> list1, list2, result(15), list3;
 list<char>::iterator res_end;
 for(int i=0; i < 5; i++) 
    list1.push_back("A"+i);
 for(int i=3; i < 10; i++) 
    list2.push_back("A"+i);
    
 show_range("Contents of list1: ", list1.begin(), list1.end());
 list3.push_back("A");
 list3.push_back("C");
 list3.push_back("D");
 
 if(includes(list1.begin(), list1.end(),list3.begin(), list3.end()))
   cout << "list3 is a subset of list1" << endl;
 else
   cout << "list3 is not a subset of list1" << endl;
 return 0;

} template<class InIter> void show_range(const char *msg, InIter start, InIter end) {

 InIter itr;
 cout << msg << endl;
 for(itr = start; itr != end; ++itr)
   cout << *itr << endl;

}

 </source>