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Algorithm search - search checks whether the sequence in the second range

Algorithm search - search checks whether the sequence in the second range


search
	
 
Header
<algorithm>

template<class ForwardIterator1, class ForwardIterator2>
ForwardIterator2 search(ForwardIterator1 first1, ForwardIterator1 last1, ForwardIterator2 first2, ForwardIterator2 last2)

search checks whether the sequence in the second range [first2, last2), is a subset of the sequence in the range [first1, last1). If found, it returns an iterator i in the range [first1, last1) that represents start of the subsequence, otherwise last1 is returned.

The non-predicate version uses operator== for comparison.

template<class ForwardIterator1, class ForwardIterator2, class BinaryPredicate>
ForwardIterator2 search(ForwardIterator1 first1, ForwardIterator1 last1, ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pr)

search checks whether the sequence in the second range [first2, last2), is a subset of the sequence in the range [first1, last1). If found, it returns an iterator i in the range [first1, last1) that represents start of the subsequence, otherwise last1 is returned.

The predicate version uses predicate function pr for comparison.


Sample

#pragma warning (disable :4786)

#include <algorithm>
#include <iostream>
#include <string>
#include <functional>

int main()
{
	int set1[5] = {10, 15, 20, 25, 30} ;
	int set2[2] = {20, 25} ;

	int* pos ;

	std::ostream_iterator<int> intOstreamIt(std::cout, ", ") ;

	std::cout << "set1 = " ;
	std::copy(set1, set1+5, intOstreamIt) ;
	std::cout << std::endl ;

	std::cout << "set2 = " ;
	std::copy(set2, set2+2, intOstreamIt) ;
	std::cout << std::endl ;
	
	//non-predicate version of search
	pos = std::search(set1, set1+5, set2, set2+2) ;

	std::cout << "\n\nusing non-predicate version of search" << std::endl ;
	std::cout << "match found at offset " << (pos - set1) << std::endl ;

	//predicate version of search
	pos = std::search(set1, set1+5, set2, set2+2, std::equal_to<int>()) ;
	std::cout << "\n\nusing predicate version of search" << std::endl ;
	std::cout << "match found at offset " << (pos - set1) << std::endl ;
	
	return 0 ;
}

Program Output

set1 = 10, 15, 20, 25, 30,
set2 = 20, 25,


using non-predicate version of search
match found at offset 2


using predicate version of search
match found at offset 2