Defined in header <algorithm>  

(1)  
template< class ForwardIt1, class ForwardIt2 > ForwardIt1 find_end( ForwardIt1 first, ForwardIt1 last, ForwardIt2 s_first, ForwardIt2 s_last );  (until C++20)  
template< class ForwardIt1, class ForwardIt2 > constexpr ForwardIt1 find_end( ForwardIt1 first, ForwardIt1 last, ForwardIt2 s_first, ForwardIt2 s_last );  (since C++20)  
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) 
(3)  
template< class ForwardIt1, class ForwardIt2, class BinaryPredicate > ForwardIt1 find_end( ForwardIt1 first, ForwardIt1 last, ForwardIt2 s_first, ForwardIt2 s_last, BinaryPredicate p );  (until C++20)  
template< class ForwardIt1, class ForwardIt2, class BinaryPredicate > constexpr ForwardIt1 find_end( ForwardIt1 first, ForwardIt1 last, ForwardIt2 s_first, ForwardIt2 s_last, BinaryPredicate p );  (since C++20)  
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 occurrence of the sequence [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>>
(until C++20) std::is_execution_policy_v<std::remove_cvref_t<ExecutionPolicy>>
(since C++20) is true.first, 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:
While the signature does not need to have 
Type requirements  
ForwardIt1 must meet the requirements of LegacyForwardIterator. 

ForwardIt2 must meet the requirements of LegacyForwardIterator. 
Iterator to the beginning of last occurrence of the sequence [s_first, s_last)
in range [first, last)
.
If no such sequence is found,  (until C++11) 
If  (since C++11) 
Does at most \(\scriptsize S\cdot(NS+1)\)S·(NS+1) comparisons where \(\scriptsize S\)S is std::distance(first2, last2)
and \(\scriptsize N\)N is std::distance(first1, last1)
.
The overloads with a template parameter named ExecutionPolicy
report errors as follows:
ExecutionPolicy
is one of the 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 (true) { ForwardIt1 new_result = std::search(first, last, s_first, s_last); if (new_result == last) { break; } 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 (true) { ForwardIt1 new_result = std::search(first, last, s_first, s_last, p); if (new_result == last) { break; } 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; auto check = [&] { result == v.end() ? std::cout << "sequence not found\n" : std::cout << "last occurrence is at: " << std::distance(v.begin(), result) << "\n"; }; std::vector<int> t1{1, 2, 3}; result = std::find_end(v.begin(), v.end(), t1.begin(), t1.end()); check(); std::vector<int> t2{4, 5, 6}; result = std::find_end(v.begin(), v.end(), t2.begin(), t2.end()); check(); }
Output:
last occurrence is at: 8 sequence not found
searches for a range of elements (function template) 

returns true if one sequence is a subsequence 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 a range for a number of consecutive copies of an element (function template) 

(C++20)  finds the last sequence of elements in a certain range (niebloid) 
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