std::min_element

Finds the smallest element in the range [first, last).

[edit] Parameters

[edit] Return value

Iterator to the smallest element in the range [first, last). If several elements in the range are equivalent to the smallest element, returns the iterator to the first such element. Returns last if the range is empty.

[edit] Complexity

Given \(\scriptsize N\)N as std::distance (first, last):

[edit] Exceptions

The overloads with a template parameter named ExecutionPolicy report errors as follows:

• If execution of a function invoked as part of the algorithm throws an exception and ExecutionPolicy is one of the standard policies, std::terminate is called. For any other ExecutionPolicy, the behavior is implementation-defined.
• If the algorithm fails to allocate memory, std::bad_alloc is thrown.

[edit] Possible implementation

template<class ForwardIt>
ForwardIt min_element(ForwardIt first, ForwardIt last)
{
 if (first == last)
 return last;
 
 ForwardIt smallest = first;
 
 while (++first != last)
 if (*first < *smallest)
 smallest = first;
 
 return smallest;
}

template<class ForwardIt, class Compare>
ForwardIt min_element(ForwardIt first, ForwardIt last, Compare comp)
{
 if (first == last)
 return last;
 
 ForwardIt smallest = first;
 
 while (++first != last)
 if (comp(*first, *smallest))
 smallest = first;
 
 return smallest;
}

[edit] Example

#include <algorithm>
#include <iostream>
#include <vector>
 
int main()
{
 std::vector <int> v{3, 1, -4, 1, 5, 9};
 
 std::vector <int>::iterator result = std::min_element(v.begin(), v.end());
 std::cout << "min element has value " << *result << " and index ["
 << std::distance (v.begin(), result) << "]\n";
}

min element has value -4 and index [2]

[edit] Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

[edit] See also