STL标准库与泛型编程-C++标准库示例

// author : Hou Jie (侯捷)
// date : 2015/10/28 
// compiler : DevC++ 5.11 (MinGW with GNU 4.9.9.2)
//
// 說明：這是侯捷 E-learning video "C++標準庫" 的實例程式.
// 該課程的所有測試都出現在此.
// 每一個小測試單元都被放進一個 namespace 中, 
// 如此保持各單元間最大的獨立性.
// 每個 namespace 上方皆有該單元相應的 #include <...> 
// 因此有可能整個程式重複含入 (included) 某些 headers. 
// 這無所謂，因為每個 standard headers 都有自我防衛機制，不讓自己被 included 二次.
//
// 本文件用到若干 C++ 2.0 New Features，所以你必須在你的集成環境 (IDE) 上設定 "C++11 on". 
// 如果你的編譯器報錯，應是因為我用到 (測試) GNU 標準庫的獨特 (非標準) 組件 (特別是 allocators)，
// 將報錯語句改為註解 (comments) 即可通過編譯. 

using namespace std;
const long ASIZE  =   500000L;

//----------------------------------------------------
#include 
#include   //snprintf()
#include  //RAND_MAX
#include  //strlen(), memcpy()
#include  
using std::cin;
using std::cout;
using std::string;

//以下 MyString 是為了測試 containers with moveable elements 效果.  
class MyString { 
public: 
    static size_t DCtor;  	//累計 default-ctor 的呼叫次數 
    static size_t Ctor;  	//累計 ctor      的呼叫次數 
    static size_t CCtor;  	//累計 copy-ctor 的呼叫次數 
    static size_t CAsgn;  	//累計 copy-asgn 的呼叫次數 
    static size_t MCtor;  	//累計 move-ctor 的呼叫次數 
    static size_t MAsgn;  	//累計 move-asgn 的呼叫次數 		    
    static size_t Dtor;	//累計 dtor 的呼叫次數 
private:     
  	char* _data; 
  	size_t _len; 
  	void _init_data(const char *s) { 
    		_data = new char[_len+1]; 
    		memcpy(_data, s, _len); 
    		_data[_len] = '\0'; 
  	} 
public: 
	//default ctor
  	MyString() : _data(NULL), _len(0) { ++DCtor;  }

	//ctor
  	MyString(const char* p) : _len(strlen(p)) { 
  		++Ctor; 
    	_init_data(p); 
  	} 

	// copy ctor
  	MyString(const MyString& str) : _len(str._len) { 
		++CCtor;  	  
    	_init_data(str._data); 	//COPY
  	} 

	//move ctor, with "noexcept"
    MyString(MyString&& str) noexcept : _data(str._data), _len(str._len)  {  
        ++MCtor;    
    	str._len = 0; 		
    	str._data = NULL;  	//避免 delete (in dtor) 
 	}
 
 	//copy assignment
  	MyString& operator=(const MyString& str) { 
    	++CAsgn;  	 
		if (this != &str) { 
    		if (_data) delete _data;  
      		_len = str._len; 
      		_init_data(str._data); 	//COPY! 
    	} 
    	else {
		    // Self Assignment, Nothing to do.   
		}
    	return *this; 
  	} 

	//move assignment
   	MyString& operator=(MyString&& str) noexcept { 	 
     	++MAsgn;   	
    	if (this != &str) { 
    		if (_data) delete _data; 
      		_len = str._len; 
      		_data = str._data;	//MOVE!
      		str._len = 0; 
      		str._data = NULL; 	//避免 deleted in dtor 
    	} 
    	return *this; 
 	}
 
 	//dtor
  	virtual ~MyString() { 	
  	    ++Dtor;	      	  	    
    	if (_data) {
    		delete _data; 	
		}
  	}   	
  	
  	bool 
  	operator<(const MyString& rhs) const	//為了讓 set 比較大小  
  	{
	   return std::string(this->_data) < std::string(rhs._data); 	//借用事實：string 已能比較大小. 
	}
  	bool 
  	operator==(const MyString& rhs) const	//為了讓 set 判斷相等. 
  	{
	   return std::string(this->_data) == std::string(rhs._data); 	//借用事實：string 已能判斷相等. 
	}	
	
	char* get() const { return _data; }
}; 
size_t MyString::DCtor=0;  	
size_t MyString::Ctor=0;  	 
size_t MyString::CCtor=0;
size_t MyString::CAsgn=0;
size_t MyString::MCtor=0;
size_t MyString::MAsgn=0;
size_t MyString::Dtor=0;

namespace std 	//必須放在 std 內 
{
template<> 
struct hash 	//這是為了 unordered containers 
{
	size_t 
	operator()(const MyString& s) const noexcept
	{  return hash()(string(s.get()));  }  
	    //借用現有的 hash (in ...\include\c++\bits\basic_string.h)
};
}
//-----------------
//以下 MyStrNoMove 是為了測試 containers with no-moveable elements 效果.  
class MyStrNoMove { 
public: 
    static size_t DCtor;  	//累計 default-ctor 的呼叫次數 
    static size_t Ctor;  	//累計 ctor      的呼叫次數 
    static size_t CCtor;  	//累計 copy-ctor 的呼叫次數 
    static size_t CAsgn;  	//累計 copy-asgn 的呼叫次數 
    static size_t MCtor;  	//累計 move-ctor 的呼叫次數 
    static size_t MAsgn;  	//累計 move-asgn 的呼叫次數 		    
    static size_t Dtor;	    //累計 dtor 的呼叫次數 
private:     
  	char* _data; 
  	size_t _len; 
  	void _init_data(const char *s) { 
    		_data = new char[_len+1]; 
    		memcpy(_data, s, _len); 
    		_data[_len] = '\0'; 
  	} 
public: 
	//default ctor
  	MyStrNoMove() : _data(NULL), _len(0) { 	++DCtor; _init_data("jjhou"); }

	//ctor
  	MyStrNoMove(const char* p) : _len(strlen(p)) { 
    	++Ctor;  _init_data(p); 
  	} 

	// copy ctor
  	MyStrNoMove(const MyStrNoMove& str) : _len(str._len) { 
		++CCtor;  	 
    	_init_data(str._data); 	//COPY
  	} 

 	//copy assignment
  	MyStrNoMove& operator=(const MyStrNoMove& str) { 
    	++CAsgn;

		if (this != &str) { 
    		if (_data) delete _data;  
      		_len = str._len; 
      		_init_data(str._data); 	//COPY! 
    	} 
    	else {
		    // Self Assignment, Nothing to do.   
		}
    	return *this; 
  	} 

 	//dtor
  	virtual ~MyStrNoMove() { 	   
  	    ++Dtor;		  	    
    	if (_data) {
    		delete _data; 	
		}
  	}   	
  	
  	bool 											
  	operator<(const MyStrNoMove& rhs) const		//為了讓 set 比較大小 
  	{
	   return string(this->_data) < string(rhs._data);  //借用事實：string 已能比較大小. 
	}  	
	
  	bool 											
  	operator==(const MyStrNoMove& rhs) const	//為了讓 set 判斷相等. 
  	{
	   return string(this->_data) == string(rhs._data);  //借用事實：string 已能判斷相等. 
	} 
		
	char* get() const { return _data; }	
}; 
size_t MyStrNoMove::DCtor=0;  	
size_t MyStrNoMove::Ctor=0;  
size_t MyStrNoMove::CCtor=0;
size_t MyStrNoMove::CAsgn=0;
size_t MyStrNoMove::MCtor=0;
size_t MyStrNoMove::MAsgn=0;
size_t MyStrNoMove::Dtor=0;

namespace std 	//必須放在 std 內 
{
template<> 
struct hash 	//這是為了 unordered containers 
{
	size_t 
	operator()(const MyStrNoMove& s) const noexcept
	{  return hash()(string(s.get()));  }  
	   //借用現有的 hash (in ...\4.9.2\include\c++\bits\basic_string.h)
};
}

//----------------------------------------------------
#include 
#include   //snprintf()
#include  //RAND_MAX
#include  
#include  
#include  
#include  
using std::cin;
using std::cout;
using std::string;
using std::max;
using std::min;

namespace jj00
{
	
bool strLonger(const string& s1, const string& s2) {
          return s1.size() < s2.size();
}		
	
void test_misc()
{
	cout << "\ntest_misc().......... \n";
     
    //以下這些是標準庫的眾多容器的 max_size() 計算方式.  
    cout << size_t(-1) << endl;					         	//4294967295
	cout << size_t(-1)/sizeof(long) << endl;		     	//1073741823
	cout << size_t(-1)/sizeof(string) << endl;	         	//1073741823
	cout << size_t(-1)/sizeof(_List_node) << endl; 	//357913941
	cout << size_t(-1)/sizeof(_Fwd_list_node) << endl; //536870911
	cout << "RAND_MAX= " << RAND_MAX << endl;	//32767
	
	cout << min( {2,5,8,9,45,0,81} ) << endl;  //0
	cout << max( {2,5,8,9,45,0,81} ) << endl;  //81
	vector v {2,5,8,9,45,0,81};               
         
	cout << "max of     zoo and hello : " 
	     << max(string("zoo"), string("hello")) << endl;              //zoo
	cout << "longest of zoo and hello : " 
	     << max(string("zoo"), string("hello"), strLonger) << endl;   //hello    
		 
	cout << hash()(MyString("Ace")) << endl;		//1765813650
	cout << hash()(MyString("Stacy")) << endl;	//2790324277
	cout << "MyString(zoo) < MyString(hello) ==> " << (MyString("zoo") < MyString("hello")) << endl;	//0
	cout << "MyString(zoo) == MyString(hello) ==> " << (MyString("zoo") == MyString("hello")) << endl;	//0	  
	cout << "MyStrNoMove(zoo) < MyStrNoMove(hello) ==> " << (MyStrNoMove("zoo") < MyStrNoMove("hello")) << endl;	 //0
	cout << "MyStrNoMove(zoo) == MyStrNoMove(hello) ==> " << (MyStrNoMove("zoo") == MyStrNoMove("hello")) << endl;	 //0
	//以上建構了 6 個 MyString objects 和 4 個 MyStrNoMove objects，都是暫時生命.    
}
}    
//--------------------------------------------------
#include   //typeid()
template
void output_static_data(const T& myStr)
{
	cout << typeid(myStr).name() << " -- " << endl; 
	cout << " CCtor=" << T::CCtor 	
		 << " MCtor=" << T::MCtor 
	     << " CAsgn=" << T::CAsgn 		 
		 << " MAsgn=" << T::MAsgn 
		 << " Dtor="  << T::Dtor 
		 << " Ctor="  << T::Ctor 
		 << " DCtor=" << T::DCtor 		 
		 << endl;	
}

#include   //clock_t, clock()
template	
void test_moveable(M c1, NM c2, long& value)
{ 	
char buf[10];
			
	//測試 move 
	cout << "\n\ntest, with moveable elements" << endl;			
	typedef typename iterator_traits::value_type  V1type; 	
clock_t timeStart = clock();								
    for(long i=0; i< value; ++i)
    {
    	snprintf(buf, 10, "%d", rand());    		
        auto ite = c1.end();
        c1.insert(ite, V1type(buf));	
	}
	cout << "construction, milli-seconds : " << (clock()-timeStart) << endl;	
	cout << "size()= " << c1.size() << endl;		
	output_static_data(*(c1.begin()));

	timeStart = clock();	
M c11(c1);						
	cout << "copy, milli-seconds : " << (clock()-timeStart) << endl;	

	timeStart = clock();	
M c12(std::move(c1));						
	cout << "move copy, milli-seconds : " << (clock()-timeStart) << endl;
		
	timeStart = clock();	
	c11.swap(c12);						
	cout << "swap, milli-seconds : " << (clock()-timeStart) << endl;		

	
	
	//測試 non-moveable 	
	cout << "\n\ntest, with non-moveable elements" << endl;		
	typedef typename iterator_traits::value_type  V2type; 				
    timeStart = clock();								
    for(long i=0; i< value; ++i)
    {
    	snprintf(buf, 10, "%d", rand());    		
        auto ite = c2.end();
        c2.insert(ite, V2type(buf));	
	}

	cout << "construction, milli-seconds : " << (clock()-timeStart) << endl;	
	cout << "size()= " << c2.size() << endl;			
	output_static_data(*(c2.begin()));

	timeStart = clock();	
NM c21(c2);						
	cout << "copy, milli-seconds : " << (clock()-timeStart) << endl;	

	timeStart = clock();	
NM c22(std::move(c2));						
	cout << "move copy, milli-seconds : " << (clock()-timeStart) << endl;
		
	timeStart = clock();	
	c21.swap(c22);						
	cout << "swap, milli-seconds : " << (clock()-timeStart) << endl;			
}	
//-----------------
long get_a_target_long()
{
long target=0;

	cout << "target (0~" << RAND_MAX << "): ";
	cin >> target;
	return target;
}

string get_a_target_string()
{
long target=0;
char buf[10];

	cout << "target (0~" << RAND_MAX << "): ";
	cin >> target;
	snprintf(buf, 10, "%d", target);
	return string(buf);
}

int compareLongs(const void* a, const void* b)
{
  return ( *(long*)a - *(long*)b );
}

int compareStrings(const void* a, const void* b)
{
  if ( *(string*)a > *(string*)b )
     	return 1;
  else if ( *(string*)a < *(string*)b )
     	return -1;  
  else      	
        return 0;  
}
//---------------------------------------------------
#include 
#include 
#include  
#include  //qsort, bsearch, NULL

namespace jj01
{
void test_array()
{
	cout << "\ntest_array().......... \n";
     
array c;  	
			
clock_t timeStart = clock();									
    for(long i=0; i< ASIZE; ++i) {
        c[i] = rand(); 
    }
	cout << "milli-seconds : " << (clock()-timeStart) << endl;	//
	cout << "array.size()= " << c.size() << endl;		
	cout << "array.front()= " << c.front() << endl;	
	cout << "array.back()= " << c.back() << endl;	
	cout << "array.data()= " << c.data() << endl;	
	
long target = get_a_target_long();

	timeStart = clock();
    ::qsort(c.data(), ASIZE, sizeof(long), compareLongs);
long* pItem = (long*)::bsearch(&target, (c.data()), ASIZE, sizeof(long), compareLongs); 
	cout << "qsort()+bsearch(), milli-seconds : " << (clock()-timeStart) << endl;	//    
  	if (pItem != NULL)
    	cout << "found, " << *pItem << endl;
  	else
    	cout << "not found! " << endl;	
}
}
//---------------------------------------------------
#include 
#include 
#include 
#include  //abort()
#include   //snprintf()
#include 
#include  
#include  	//sort()
namespace jj02
{
void test_vector(long& value)
{
	cout << "\ntest_vector().......... \n";
     
vector c;  	
char buf[10];
			
clock_t timeStart = clock();								
    for(long i=0; i< value; ++i)
    {
    	try {
    		snprintf(buf, 10, "%d", rand());
        	c.push_back(string(buf));     		
		}
		catch(exception& p) {
			cout << "i=" << i << " " << p.what() << endl;	
			     //曾經最高 i=58389486 then std::bad_alloc
			abort();
		}
	}
	cout << "milli-seconds : " << (clock()-timeStart) << endl;	
	cout << "vector.max_size()= " << c.max_size() << endl;	//1073747823
	cout << "vector.size()= " << c.size() << endl;		
	cout << "vector.front()= " << c.front() << endl;	
	cout << "vector.back()= " << c.back() << endl;	
	cout << "vector.data()= " << c.data() << endl;
	cout << "vector.capacity()= " << c.capacity() << endl << endl;		

																				
string target = get_a_target_string();
    {
	timeStart = clock();
auto pItem = find(c.begin(), c.end(), target);
	cout << "std::find(), milli-seconds : " << (clock()-timeStart) << endl;  
	 
  	if (pItem != c.end())
    	cout << "found, " << *pItem << endl << endl;
  	else
    	cout << "not found! " << endl << endl;
    }

	{
	timeStart = clock();
    sort(c.begin(), c.end());
	cout << "sort(), milli-seconds : " << (clock()-timeStart) << endl; 
	
	timeStart = clock();	    
string* pItem = (string*)::bsearch(&target, (c.data()), 
                                   c.size(), sizeof(string), compareStrings); 
	cout << "bsearch(), milli-seconds : " << (clock()-timeStart) << endl; 
	   
  	if (pItem != NULL)
    	cout << "found, " << *pItem << endl << endl;
  	else
    	cout << "not found! " << endl << endl;	
	}
	
	c.clear();
	test_moveable(vector(),vector(), value);	
}	
}
//---------------------------------------------------
#include 
#include 
#include 
#include  //abort()
#include   //snprintf()
#include  //find()
#include 
#include  
namespace jj03
{
void test_list(long& value)
{
	cout << "\ntest_list().......... \n";
     
list c;  	
char buf[10];
			
clock_t timeStart = clock();							
    for(long i=0; i< value; ++i)
    {
    	try {
    		snprintf(buf, 10, "%d", rand());
        	c.push_back(string(buf));    	
		}
		catch(exception& p) {
			cout << "i=" << i << " " << p.what() << endl;	
			abort();
		}
	}
	cout << "milli-seconds : " << (clock()-timeStart) << endl;		
	cout << "list.size()= " << c.size() << endl;
	cout << "list.max_size()= " << c.max_size() << endl;    //357913941
	cout << "list.front()= " << c.front() << endl;	
	cout << "list.back()= " << c.back() << endl;		
		
string target = get_a_target_string();		
    timeStart = clock();		
auto pItem = find(c.begin(), c.end(), target);						
	cout << "std::find(), milli-seconds : " << (clock()-timeStart) << endl;		
	
  	if (pItem != c.end())
    	cout << "found, " << *pItem << endl;
  	else
    	cout << "not found! " << endl;	
    	
    timeStart = clock();		
	c.sort();						
	cout << "c.sort(), milli-seconds : " << (clock()-timeStart) << endl;		    	
    	
	c.clear();
	test_moveable(list(),list(), value);								
}	
}
//---------------------------------------------------
#include 
#include 
#include 
#include  //abort()
#include   //snprintf()
#include 
#include  
namespace jj04
{
void test_forward_list(long& value)
{
	cout << "\ntest_forward_list().......... \n";
     
forward_list c;  	
char buf[10];
			
clock_t timeStart = clock();								
    for(long i=0; i< value; ++i)
    {
    	try {
    		snprintf(buf, 10, "%d", rand());
        	c.push_front(string(buf));  			   		
		}
		catch(exception& p) {
			cout << "i=" << i << " " << p.what() << endl;	
			abort();
		}
	}
	cout << "milli-seconds : " << (clock()-timeStart) << endl;	
	cout << "forward_list.max_size()= " << c.max_size() << endl;  //536870911
	cout << "forward_list.front()= " << c.front() << endl;	


string target = get_a_target_string();	
    timeStart = clock();			
auto pItem = find(c.begin(), c.end(), target);	
	cout << "std::find(), milli-seconds : " << (clock()-timeStart) << endl;		
	
	if (pItem != c.end())
    	cout << "found, " << *pItem << endl;
  	else
    	cout << "not found! " << endl;	
    	
    timeStart = clock();		
	c.sort();						
	cout << "c.sort(), milli-seconds : " << (clock()-timeStart) << endl;		
	
	c.clear();	 
}											 
}
//---------------------------------------------------
#include 
#include 
#include 
#include  //abort()
#include   //snprintf()
#include 
#include  
namespace jj05
{
void test_deque(long& value)
{
	cout << "\ntest_deque().......... \n";
     
deque c;  	
char buf[10];
			
clock_t timeStart = clock();								
    for(long i=0; i< value; ++i)
    {
    	try {
    		snprintf(buf, 10, "%d", rand());
        	c.push_back(string(buf));    			 		
		}
		catch(exception& p) {
			cout << "i=" << i << " " << p.what() << endl;	
			abort();
		}
	}
	cout << "milli-seconds : " << (clock()-timeStart) << endl;		
	cout << "deque.size()= " << c.size() << endl;
	cout << "deque.front()= " << c.front() << endl;	
	cout << "deque.back()= " << c.back() << endl;	
	cout << "deque.max_size()= " << c.max_size() << endl;	//1073741821	
	
string target = get_a_target_string();	
    timeStart = clock();			
auto pItem = find(c.begin(), c.end(), target);	
	cout << "std::find(), milli-seconds : " << (clock()-timeStart) << endl;	
	
	if (pItem != c.end())
    	cout << "found, " << *pItem << endl;
  	else
    	cout << "not found! " << endl;	
    	
    timeStart = clock();		
	sort(c.begin(), c.end());						
	cout << "sort(), milli-seconds : " << (clock()-timeStart) << endl;		
	
	c.clear();
	test_moveable(deque(),deque(), value);		 						
}															
}
//---------------------------------------------------
#include 
#include 
#include 
#include  //abort()
#include   //snprintf()
#include 
#include  
namespace jj06
{
void test_multiset(long& value)
{
	cout << "\ntest_multiset().......... \n";
	
multiset c;  	
char buf[10];		
clock_t timeStart = clock();								
    for(long i=0; i< value; ++i)
    {
    	try {
    		snprintf(buf, 10, "%d", rand());
        	c.insert(string(buf));     				
		}
		catch(exception& p) {
			cout << "i=" << i << " " << p.what() << endl;	
			abort();
		}
	}
	cout << "milli-seconds : " << (clock()-timeStart) << endl;	
	cout << "multiset.size()= " << c.size() << endl;	
	cout << "multiset.max_size()= " << c.max_size() << endl;	//214748364
	
string target = get_a_target_string();	
	{
    timeStart = clock();
auto pItem = find(c.begin(), c.end(), target);	//比 c.find(...) 慢很多	
	cout << "std::find(), milli-seconds : " << (clock()-timeStart) << endl;		
	if (pItem != c.end())
    	cout << "found, " << *pItem << endl;
  	else
    	cout << "not found! " << endl;	
 	}
 	
 	{
    timeStart = clock();		
auto pItem = c.find(target);		//比 std::find(...) 快很多							
	cout << "c.find(), milli-seconds : " << (clock()-timeStart) << endl;		 
	if (pItem != c.end())
    	cout << "found, " << *pItem << endl;
  	else
    	cout << "not found! " << endl;	
 	}	
	 
	c.clear();
	test_moveable(multiset(),multiset(), value);	 						
}															 
}
//---------------------------------------------------
#include