Sorts some of the elements in the range[first, last) in ascending order, storing the result in the range[d_first, d_last).

At mostd_last- d_first of the elements are placed sorted to the range[d_first, d_first+ n).n is the number of elements to sort (std::min(std::distance(first, last), d_last- d_first)). The order of equal elements is not guaranteed to be preserved.

If*first is notwritable tod_first, the program is ill-formed.

If any of the following conditions is satisfied, the behavior is undefined:

[edit]Parameters

[edit]Return value

An iterator to the element defining the upper boundary of the sorted range, i.e.d_first+std::min(std::distance(first, last), d_last- d_first).

[edit]Complexity

Given\(\scriptsize N\)N asstd::distance(first, last),\(\scriptsize D\)D asd_last- d_first:

[edit]Exceptions

The overloads with a template parameter namedExecutionPolicy report errors as follows:

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

[edit]Possible implementation

See also the implementations inlibstdc++ andlibc++.

[edit]Example

#include <algorithm>#include <functional>#include <iostream>#include <string_view>#include <type_traits>#include <vector> void println(std::string_view rem,constauto& v){std::cout<< rem;ifconstexpr(std::is_scalar_v<std::decay_t<decltype(v)>>)std::cout<< v;elsefor(int e: v)std::cout<< e<<' ';std::cout<<'\n';} int main(){constauto v0={4,2,5,1,3};std::vector<int> v1{10,11,12};std::vector<int> v2{10,11,12,13,14,15,16};std::vector<int>::iterator it;     it= std::partial_sort_copy(v0.begin(), v0.end(), v1.begin(), v1.end());    println("Writing to the smaller vector in ascending order gives: ", v1); if(it== v1.end())        println("The return value is the end iterator",' ');     it= std::partial_sort_copy(v0.begin(), v0.end(), v2.begin(), v2.end(),std::greater<int>());     println("Writing to the larger vector in descending order gives: ", v2);    println("The return value is the iterator to ",*it);}

Writing to the smaller vector in ascending order gives: 1 2 3The return value is the end iteratorWriting to the larger vector in descending order gives: 5 4 3 2 1 15 16The return value is the iterator to 15

[edit]Defect reports

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

[edit]See also

• In other languages

• Deutsch
• Español
• Français
• Italiano
• 日本語
• Português
• Русский
• 中文