Defined in header <algorithm>  

template< class ForwardIt1, class ForwardIt2 > ForwardIt1 find_end( ForwardIt1 first, ForwardIt1 last, ForwardIt2 s_first, ForwardIt2 s_last );  (1)  
template< class ExecutionPolicy, class ForwardIt1, class ForwardIt2 > ForwardIt1 find_end( ExecutionPolicy&& policy, ForwardIt1 first, ForwardIt1 last, ForwardIt2 s_first, ForwardIt2 s_last );  (2)  (since C++17) 
template< class ForwardIt1, class ForwardIt2, class BinaryPredicate > ForwardIt1 find_end( ForwardIt1 first, ForwardIt1 last, ForwardIt2 s_first, ForwardIt2 s_last, BinaryPredicate p );  (3)  
template< class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class BinaryPredicate > ForwardIt1 find_end( ExecutionPolicy&& policy, ForwardIt1 first, ForwardIt1 last, ForwardIt2 s_first, ForwardIt2 s_last, BinaryPredicate p );  (4)  (since C++17) 
Searches for the last subsequence of elements [s_first, s_last)
in the range [first, last)
.
operator==
.p
.policy
. These overloads do not participate in overload resolution unless std::is_execution_policy_v<std::decay_t<ExecutionPolicy>>
is truefirst, last    the range of elements to examine 
s_first, s_last    the range of elements to search for 
policy    the execution policy to use. See execution policy for details. 
p    binary predicate which returns true if the elements should be treated as equal. The signature of the predicate function should be equivalent to the following:
The signature does not need to have 
Type requirements  
ForwardIt1 must meet the requirements of ForwardIterator . 

ForwardIt2 must meet the requirements of ForwardIterator . 
Iterator to the beginning of last subsequence [s_first, s_last)
in range [first, last)
.
If no such subsequence is found,  (until C++11) 
If  (since C++11) 
Does at most S*(NS+1)
comparisons where S = distance(s_first, s_last)
and N = distance(first, last)
.
The overloads with a template parameter named ExecutionPolicy
report errors as follows:
ExecutionPolicy
is one of the three standard policies, std::terminate
is called. For any other ExecutionPolicy
, the behavior is implementationdefined. std::bad_alloc
is thrown. First version 

template<class ForwardIt1, class ForwardIt2> ForwardIt1 find_end(ForwardIt1 first, ForwardIt1 last, ForwardIt2 s_first, ForwardIt2 s_last) { if (s_first == s_last) return last; ForwardIt1 result = last; while (1) { ForwardIt1 new_result = std::search(first, last, s_first, s_last); if (new_result == last) { return result; } else { result = new_result; first = result; ++first; } } return result; } 
Second version 
template<class ForwardIt1, class ForwardIt2, class BinaryPredicate> ForwardIt1 find_end(ForwardIt1 first, ForwardIt1 last, ForwardIt2 s_first, ForwardIt2 s_last, BinaryPredicate p) { if (s_first == s_last) return last; ForwardIt1 result = last; while (1) { ForwardIt1 new_result = std::search(first, last, s_first, s_last, p); if (new_result == last) { return result; } else { result = new_result; first = result; ++first; } } return result; } 
The following code uses find_end()
to search for two different sequences of numbers.
#include <algorithm> #include <iostream> #include <vector> int main() { std::vector<int> v{1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4}; std::vector<int>::iterator result; std::vector<int> t1{1, 2, 3}; result = std::find_end(v.begin(), v.end(), t1.begin(), t1.end()); if (result == v.end()) { std::cout << "subsequence not found\n"; } else { std::cout << "last subsequence is at: " << std::distance(v.begin(), result) << "\n"; } std::vector<int> t2{4, 5, 6}; result = std::find_end(v.begin(), v.end(), t2.begin(), t2.end()); if (result == v.end()) { std::cout << "subsequence not found\n"; } else { std::cout << "last subsequence is at: " << std::distance(v.begin(), result) << "\n"; } }
Output:
last subsequence is at: 8 subsequence not found
searches for a range of elements (function template) 

returns true if one set is a subset of another (function template) 

finds the first two adjacent items that are equal (or satisfy a given predicate) (function template) 

(C++11)  finds the first element satisfying specific criteria (function template) 
searches for any one of a set of elements (function template) 

searches for a number consecutive copies of an element in a range (function template) 
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