The C++ Standard Library consists of the header, <algorithm> which defines a collection of functions (principally designed to deal with a range of elements). binary_search() is a method in the STL that tests if a certain value exists in sorted sequence.
Syntax:
binary_search( iterator_begin, iterator_end, val ); binary_search( iterator_begin, iterator_end, val, comparator );
Parameters: The binary_search() method accepts 4 parameters
- iterator_begin: Iterator to the initial position
- iterator_end: Iterator to the final position ( Note: the range is [iterator_begin,iterator_end) )
- val: Value to search
- comparator: binary predicate which returns true if the first argument is less than the second.
Return value: True if val is found. False otherwise
Example of binary_search() method
#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;
int main()
{
vector<int> v;
v.push_back(1);
v.push_back(2);
v.push_back(3);
v.push_back(4);
v.push_back(5);
v.push_back(6);
if(binary_search(v.begin(), v.end(), 4))
cout<<"4 is found! \n";
if(!binary_search(v.begin(), v.end(), 7))
cout<<"7 not found! \n";
}
Output:
4 is found! 7 not found!
