cb51a_c++_STL_算法_根据第n个元素排序nth_element

cb51a_c++_STL_算法_根据第n个元素排序nth_element

nth_element(b,n,e),比如最大的5个数排序，或者最小的几个数

nth_element(b,n,e,p)

对比：partition()算法，分区算法

error C2675: 一元“++”:“TT88”不定义该运算符或到预定义运算符可接收类型的转换

for (TT88::iterator iter = ideq.begin(); iter != ideq.end(); ++ideq),写错了，应该是++iter

/*cb51a_c++_STL_算法_根据第n个元素排序nth_element
nth_element(b,n,e),比如最大的5个数排序，或者最小的几个数
nth_element(b,n,e,p)
对比：partition()算法，分区算法


error C2675: 一元“++”:“TT88”不定义该运算符或到预定义运算符可接收类型的转换
for (TT88::iterator iter = ideq.begin(); iter != ideq.end(); ++ideq),写错了，应该是++iter
*/

#include <iostream>
#include <algorithm>
#include <deque>
#include <iterator>
#include <functional>

using namespace std;

template <class TT88>
void print88(TT88 &ideq)
{
	for (TT88::iterator iter = ideq.begin(); iter != ideq.end(); ++iter)
		cout << *iter << ' ';
	cout << endl;
}

int main()
{
	deque<int> ideq,ideq2;
	for (int i = 3; i <= 7; ++i)
		ideq.push_back(i);
	for (int i = 2; i <= 6; ++i)
		ideq.push_back(i);
	for (int i = 1; i <= 5; ++i)
		ideq.push_back(i);
	ideq2 = ideq;

	print88(ideq);
	nth_element(ideq.begin(), ideq.begin() + 3, ideq.end());//默认less<int>(),升序
	cout << "nth_element排序后：" << endl;
	print88(ideq);

	cout << "用copy，到输出流迭代器显示：" << endl;
	copy(ideq.begin(), ideq.begin() + 4, ostream_iterator<int>(cout, " "));
	cout << endl;

	ideq = ideq2;
	nth_element(ideq.begin(), ideq.begin() + 1, ideq.end(),greater<int>());//降序，大到小
	cout << "降序：" << endl;
	print88(ideq);

	deque<int>::iterator pos;
	//pos = partition(ideq.begin(), ideq.end(), bind2nd(greater<int>(), 3));
	cout << endl;
	ideq = ideq2;
	cout << "分区partition小于等于3放左边，其余放右边" << endl;
	pos = partition(ideq.begin(), ideq.end(), bind2nd(less_equal<int>(), 3));
	print88(ideq);
	copy(ideq.begin(), pos, ostream_iterator<int>(cout, " "));
	return 0;      
}