C++ Tutorial/STL Algorithms Merge/includes
Container includes: generic includes algorithm
<source lang="cpp">#include <iostream>
- include <cassert>
- include <algorithm>
- 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;
- include <algorithm>
- 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. */
- include <iostream>
- include <vector>
- include <deque>
- include <list>
- include <set>
- include <map>
- include <string>
- include <algorithm>
- include <iterator>
- include <functional>
- 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