std:: min_element

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

Parameters

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.

Complexity

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

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.

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;
}

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]

Defect reports

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

See also