layout: post

title: 侯捷STL学习（十一）

date: 2017-07-24

tag: 侯捷STL

第三讲标准库内核分析-算法

标准库算法形式

iterator分类

不同容器iterator类型不同
测试iterator类型

#include <iostream>     // std::cout

#include <iterator>     // std::iterator_traits

#include <typeinfo>     // typeid

namespace jj33

{

void _display_category(random_access_iterator_tag)

{   cout << "random_access_iterator" << endl; }

void _display_category(bidirectional_iterator_tag)

{   cout << "bidirectional_iterator" << endl; }

void _display_category(forward_iterator_tag)

{   cout << "forward_iterator" << endl;  }

void _display_category(output_iterator_tag)

{   cout << "output_iterator" << endl;   }

void _display_category(input_iterator_tag)

{   cout << "input_iterator" << endl;    }

template<typename I>

void display_category(I itr)

{

   typename iterator_traits<I>::iterator_category cagy;

   _display_category(cagy);

   cout << "typeid(itr).name()= " << typeid(itr).name() << endl << endl;

       //The output depends on library implementation.

       //The particular representation pointed by the

	   //returned valueis implementation-defined,

	   //and may or may not be different for different types.

}

void test_iterator_category()

{

	cout << "\ntest_iterator_category().......... \n";

  	display_category(array<int,10>::iterator());

  	display_category(vector<int>::iterator());

  	display_category(list<int>::iterator());

  	display_category(forward_list<int>::iterator());

  	display_category(deque<int>::iterator());

  	display_category(set<int>::iterator());

  	display_category(map<int,int>::iterator());

  	display_category(multiset<int>::iterator());

  	display_category(multimap<int,int>::iterator());

  	display_category(unordered_set<int>::iterator());

  	display_category(unordered_map<int,int>::iterator());

  	display_category(unordered_multiset<int>::iterator());

  	display_category(unordered_multimap<int,int>::iterator());	  

  	display_category(istream_iterator<int>());

  	display_category(ostream_iterator<int>(cout,""));

}

}