nth_element

template <class RandomAccessIterator>
void nth_element(RandomAccessIterator first,RandomAccessIterator middle,RandomAccessIterator last);

template <class RandomAccessIterator,class StrickWeakOrdering>
void nth_element(RandomAccessIterator first,RandomAccessIterator middle,RandomAccessIterator last,StrickWeakOrdering cmp);

　　这里唯一的保证是数组被分为两段，第一段内的任何元素都不大于第二段，而每段中的内部排序并非重点

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main()
{
    vector<int> v{13,1,2,6,9,-1,-7,10,20};
    nth_element(v.begin(),v.begin()+5,v.end());
    for_each(v.begin(),v.end(),[](int i)
    {
        cout<<i<<" ";
    });
    cout<<endl;
    return 0;
}

标签：begin,RandomAccessIterator,int,element,nth,include
来源： https://www.cnblogs.com/tianzeng/p/10390886.html