The C++ Standard Library consists of the header, <algorithm>
which defines a collection of functions (principally designed to deal with a range of elements). includes()
is a method in the STL that tests whether a sorted range includes another sorted range.
Syntax:
includes( iterator_begin1, iterator_end1, iterator_begin2, iterator_end2, comparator); //comparator is optional
Parameters: The includes()
method accepts 5 parameters
- iterator_begin1, iterator_end1: Iterator to the initial and final position of first sorted sequence ( Note: the range is [iterator_begin1, iterator_end1) )
- iterator_begin2, iterator_end2: Iterator to the initial and final position of second sorted sequence ( Note: the range is [iterator_begin2, iterator_end2) )
- comparator: Binary function that accepts two elements in the range as arguments, and returns a value convertible to bool.
Return value: true if second range is included in the first range, false otherwise
Example of includes() method
#include <iostream> #include <algorithm> #include <vector> using namespace std; int main () { vector<int> v1; v1.push_back(5); v1.push_back(6); v1.push_back(3); v1.push_back(1); v1.push_back(2); vector<int> v2; v2.push_back(3); v2.push_back(1); v2.push_back(2); sort (v1.begin(),v1.end()); // 1 2 3 5 6 sort (v2.begin(),v2.end()); // 1 2 3 if(includes(v1.begin(), v1.end(), v2.begin(), v2.end())) cout<<"V1 includes V2"; }
Output:
V1 includes V2