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【C++】string模拟实现

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目录

前言

    💬 hello! 各位铁子们大家好哇。

             今日更新了string模拟实现的内容
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构造

初始化列表部分，要开辟新空间初始化。三次调用strlen效率太低，改进如下图：

我们的构造函数直接写一个全缺省的，这样就不用分开写无参和有参的构造了。上面缺省值不能给nullptr，因为初始化列表那里会报错，str为空，无法strlen。缺省值也不能给’\0’，而要给”\0″，因为’\0’的类型是char，不能给char*。其实给”\0″也是多余的，虽然可以这样写，我们可以直接给空字符串””，系统会在后面自动加上”\0″的。

		string(const char* str="")
			: _size(strlen(str))
		{
			_capacity = _size;
			_str = new char[_capacity + 1];
			strcpy(_str, str);
		}

 析构

		~string()
		{
			delete[] _str;
			_str = nullptr;
			_size = _capacity = 0;
		}

遍历

//遍历
size_t size() const
{
	return _size;
}

size_t capacity() const 
{
	return _capacity;
}

char& operator[](size_t pos) 
{
	assert(pos < _size);
	return _str[pos];   //_str[pos]在堆上，可用引用返回，支持修改
}

const char& operator[](size_t pos) const
{
	assert(pos < _size);
	return _str[pos];   
}

void test_string1()
{
	string s1("hello world");
	string s2;

	for (size_t i = 0; i < s1.size(); i++)
	{
		s1[i]++;
	}
	cout << endl;

	for (size_t i = 0; i < s1.size(); i++)
	{
		cout << s1[i] << "";
	}
	cout << endl;

	const string s3("xxxx");
	for (size_t i = 0; i < s3.size(); i++)
	{
		//s3[i]++      错误，可读，但不能写
		cout << s3[i] << "";
	}
	cout << endl;
}

operator[]需要重载两个，因为string对象可能是const修饰的。 

迭代器

typedef char* iterator;

iterator begin()
{
	return _str;
}

iterator end()
{
	return _str + _size;
}

void test_string2()
{
	string s3("hello world");
	string::iterator it3 = s3.begin();
	while (it3 != s3.end())
	{
		//*it3 -= 3;
		cout << *it3 << " ";
		++it3;
	}
	cout << endl;

	for (auto ch : s3)
	{
		cout << ch << " ";
	}
	cout << endl;

}

这里迭代器的模拟实现是容易的，不同的容器有不同的迭代器，只是名字相同。

如果string对象有const修饰时，就需要const迭代器，如下方代码：

typedef const char* const_iterator;

const_iterator begin() const
{
	return _str;
}

const_iterator end() const
{
	return _str + _size;
}

const string s2("hello world");
string::const_iterator it2 = s2.begin(); 
while (it2 != s2.end())
{
	cout << *it2 << " ";
	++it2;
}
cout << endl;

插入

	void reserve(size_t n)
	{
		if (n > _capacity)
		{
			char* tmp = new char[n+1];
			strcpy(tmp, _str);
			delete[] _str;
			_str = tmp;
			
			_capacity = n;
		}

	}

	void push_back(char ch)
	{
/*		if (_size == _capacity)
		{
			reserve(_capacity == 0 ? 4 : 2 * _capacity);
		}
		_str[_size] = ch;
		++_size;
		_str[_size] = '\0';*/
		insert(_size, ch);
	}

	void append(const char* str)
	{
/*		size_t len = strlen(str);
		if (_size + len > _capacity)
		{
			reserve(_size + len);
		}
		strcpy(_str + _size, str);
		_size += len;*/
		insert(_size, str);

	}

	string& operator+=(char ch)
	{
		push_back(ch);
		return *this;
	}

	string& operator+=(const char* str)
	{ 
		append(str);
		return *this;
	}

void insert(size_t pos, char ch)
{
	assert(pos <= _size);
	if (_size == _capacity)
	{
		reserve(_capacity == 0 ? 4 : 2 * _capacity);
	}

	//第一种写法
	/*int end = _size;
	while (end >= (int) pos)  //需要强转，pos是size_t类型，end是int，end会被转成size_t类型，即范围小会转向范围大的。
	{						  //当pos等于0，即头插时。结束条件为end小于0，如果不强转，当end小于0时，又会被转成无符号的
		_str[end + 1] = _str[end];  //就会死循环
		--end;
	}*/

	//第二种
	size_t end = _size+1;
	while (end > pos)
	{
		_str[end] = _str[end-1];
		--end;
	}
	_str[pos] = ch;
	++_size;
}

void insert(size_t pos, const char* str)
{
	assert(pos <= _size);
	size_t len = strlen(str);
	if (_size + len > _capacity)
	{
		reserve(_size + len);
	}

	size_t end = _size + len;
	while (end > pos + len - 1)
	{
		_str[end] = _str[end - len];
		end--;
	}
	strncpy(_str + pos, str, len);
	_size += len;
}

void test_string3()
{
	string s3("hello world"); 
	s3.push_back('1'); 
	s3.push_back('2');  

	cout << s3.c_str()<< endl; 

	s3 += 'x';  
	s3 += "yyyy"; 
	cout << s3.c_str() << endl; 

	string s1("hello world");
	s1.insert(11, 'x');
	cout << s1.c_str() << endl;

	s1.insert(0, 'x');
	cout << s1.c_str() << endl;
}

void test_string6()
{
	string s1("hello world");
	cout << s1.c_str() << endl;

	s1.insert(6, "xxxx");
	cout << s1.c_str() << endl;
}

删除、改变容量、赋值

		const char* c_str() const
		{
			return _str;
		}

	   	void resize(size_t n, char ch = '\0')
		{
			if (n < _size)
			{
				_str[n] = '\0';
				_size = n;
			}
			else
			{
				reserve(n);
				for (size_t i = _size; i < n; i++)
				{
					_str[i] = ch;
				}
				_str[n] = '\0';
				_size = n;
			}
		}

	void erase(size_t pos, size_t len = npos)
	{
		assert(pos < _size);
		if (len == npos || len >= _size - pos)  //len +pos>= _size  不能这么写，会有溢出风险
		{
			_str[pos] = '\0';
			_size = pos;
		}
		else
		{
			strcpy(_str + pos, _str + pos + len);
			_size -= len;
		}
	}

		//s2(s1)
		string(const string& s)
		{
			_str = new char[s._capacity + 1];
			strcpy(_str, s._str);
			_size = s._size;
			_capacity = s._capacity;
		}

		//s1=s3
		string& operator=(const string& s)
		{
			char* tmp = new char[s._capacity+1];
			strcpy(tmp, s._str);

			delete[] _str;
			_str = tmp;
			_size = s._size;
			_capacity = s._capacity;
			
			return *this;
		}

void test_string4()
{
	string s1("hello world");
	cout << s1.c_str() << endl;
	
	s1.erase(6, 3);
	cout << s1.c_str() << endl;

	string s2("hello world");
	cout << s2.c_str() << endl;

	s2.resize(5);
	cout << s2.c_str() << endl;

	s2.resize(20, 'x');
	cout << s2.c_str() << endl;

}

	void test_string5()
	{
		string s1("hello world");
		cout << s1.c_str() << endl;

		string s2(s1);
		cout << s2.c_str() << endl;
		
		string s3("xxxxx");
		s1 = s3;
		cout << s1.c_str() << endl;
		cout << s3.c_str() << endl;
	}

交换

当我们用算法库里面的模板swap时，效率很低，它会进行3次拷贝+1次析构。我们需要自己手写一个成员函数swap提高效率。 如下图：

为了避免有人使用效率不高的swap，其实还有一个全局的swap，如下图：

 查找

		size_t find(char ch, size_t pos = 0) const
		{
			assert(pos < _size);
			for (size_t i = pos; i < _size; i++)
			{
				if (_str[i] == ch)
					return i;
			}
			return npos;
		}

		size_t find(const char* sub, size_t pos = 0) const
		{
			assert(pos < _size);

			const char* p = strstr(_str+pos, sub);
			if (p)
			{
				return p - _str;
			}
			else
			{
				return npos;
			} 
		}

		string substr(size_t pos = 0, size_t len = npos)
		{
			string sub;
			if (len >= _size - pos)
			{
				for (size_t i = pos; i < _size; i++)
				{
					sub += _str[i];
				}
			}
			else
			{
				for (size_t i = pos; i < pos+len; i++)
				{
					sub += _str[i];
				}
			}
			return sub;
		}

void test_string7()
{
	string url1("https://legacy.cplusplus.com/reference/string/string/substr/");
	string url2("https://www.baidu.com/s?ie=utf-8&f=8&rsv_bp=1&rsv_idx=1&tn=baidu&wd=%E5%90%8E%E7%BC%80%20%E8%8B%B1%E6%96%87&fenlei=256&rsv_pq=0xc61b98d100494ef5&rsv_t=b494uh2Bd6SIxMQ1XY4CwB9MZOD%2BaMk5sx8aiT0NAgUczCRAy8jK7PvP5rxt&rqlang=en&rsv_enter=1&rsv_dl=tb&rsv_sug3=23&rsv_sug1=17&rsv_sug7=100&rsv_sug2=0&rsv_btype=i&inputT=7123&rsv_sug4=8008");

	string protocol, domain, uri; 
	size_t i1 = url1.find(':');  
	if (i1 != string::npos) 
	{
		protocol = url1.substr(0, i1 - 0);//左闭右开，减去后就是个数 
		cout << protocol.c_str() << endl; 
	}

	size_t i2 = url1.find('/',i1+3); 
	if (i2 != string::npos)  
	{
		domain = url1.substr(i1+3, i2-(i1+3));//左闭右开，减去后就是个数 
		cout << domain.c_str() << endl; 
		 
		uri = url1.substr(i2 + 1); 
		cout << uri.c_str() << endl; 
	}
}

运算符重载

		void clear()
		{
			_size = 0;
			_str[_size] = '\0';
		}

	bool operator==(const string& s1, const string& s2)
	{
		int ret = strcmp(s1.c_str(), s2.c_str());
		return ret == 0;
	}

	bool operator<(const string& s1, const string& s2)
	{
		int ret = strcmp(s1.c_str(), s2.c_str());
		return ret < 0;
	}

	bool operator<=(const string& s1, const string& s2)
	{
		return s1 < s2 || s1 == s1;
	}

	bool operator>(const string& s1, const string& s2)
	{
		return !(s1 <= s2);
	}

	bool operator>=(const string& s1, const string& s2)
	{
		return !(s1 < s2);
	}

	bool operator!=(const string& s1, const string& s2)
	{
		return !(s1 == s2);
	}

	ostream& operator<<(ostream& out, const string& s)
	{
		for (auto ch : s)
		{
			out << ch;
		}
		return out;
	}

	istream& operator>>(istream& in, string& s) 
	{
		s.clear(); 
		char ch;
		//in >> ch; 错误，C++规定 cin,scanf默认空格和换行是分隔符，
		ch = in.get();//不会取到,get才能取到
		char buff[128];
		size_t i = 0;
		while (ch != ' ' && ch != '\n')
		{
			buff[i++] = ch;
			if (i == 127)
			{
				buff[127] = '\0';
				s += buff;
				i = 0;
			}
			ch = in.get();
		}
		if (i > 0)
		{
			buff[i] = '\0';
			s += buff; 
		}
		return in;
	}


	istream& getline(istream& in, string& s)
	{
		s.clear();
		char ch;
		//in >> ch; 错误，C++规定 cin,scanf默认空格和换行是分隔符，
		ch = in.get();//不会取到,get才能取到
		while (ch != '\n')
		{
			s += ch;
			ch = in.get();
		}
		return in;
	}

	void test_string8()
	{
		string s1("hello world");
		string s2("hello world");

		cout << (s1 == s2) << endl;

		cout << ("hello world" == s2) << endl;//因为重载成全局的函数，
		cout << (s2 == "hello world") << endl;//单参数构造支持隐式类型转换。

		cout << s1 << endl;
		cout << s2 << endl;

		cin >> s1 >> s2;

		cout << s1 << endl;
		cout << s2 << endl;

		getline(cin, s1);
		cout << s1 << endl;

	}

现代写法

拷贝构造 

		//现代写法
		string(const string& s)
		{
			string tmp(s._str);
			swap(tmp);
		}

 赋值

		string& operator=(string tmp)
		{
			//现代写法
			swap(tmp);
			return *this;
		}

完整代码呈现

头文件

#pragma once
#include<assert.h>

namespace bit
{
	class string
	{
	public:
		typedef char* iterator;
		typedef const char* const_iterator;

		const_iterator begin() const
		{
			return _str;
		}

		const_iterator end() const
		{
			return _str + _size;
		}
		iterator begin()
		{
			return _str;
		}

		iterator end()
		{
			return _str + _size;
		}
		//string()
		//	:_str(nullptr)
		//	,_size(0)
		//	,_capacity(0)
		//{}
		 
		_str(str)   错误，这样的话声明部分就得加上const，加上后又会导致不能修改   
		//string(const char* str)
		//	:_str(new char[strlen(str)+1])  //必须自己开辟新的空间，
		//	,_size(strlen(str))          //调用三次strlen，效率不高
		//	,_capacity(strlen(str))
		//{
		//	strcpy(_str, str);
		//}

		const char* c_str() const
		{
			return _str;
		}

		//string(const char* str = "\0")  里面不能写const char* str =nullptr
		string(const char* str="")
			: _size(strlen(str))
		{
			_capacity = _size;
			_str = new char[_capacity + 1];
			strcpy(_str, str);
		}

		//s2(s1)   传统写法
		//string(const string& s)
		//{
		//	_str = new char[s._capacity + 1];
		//	strcpy(_str, s._str);
		//	_size = s._size;
		//	_capacity = s._capacity;
		//}
		
		//现代写法
		string(const string& s)
		{
			string tmp(s._str);
			swap(tmp);
		}

		string& operator=(string tmp)
		{ 
			//现代写法
			swap(tmp);
			return *this;
		}

		//s1=s3  传统写法
		//string& operator=(const string& s)
		//{
		//	char* tmp = new char[s._capacity+1];
		//	strcpy(tmp, s._str);

		//	delete[] _str;
		//	_str = tmp;
		//	_size = s._size;
		//	_capacity = s._capacity;
		//	
		//	return *this;
		//}

		~string()
		{
			delete[] _str;
			_str = nullptr;
			_size = _capacity = 0;
		}

		//遍历
		size_t size() const
		{
			return _size;
		}

		size_t capacity() const 
		{
			return _capacity;
		}

		char& operator[](size_t pos) 
		{
			assert(pos < _size);
			return _str[pos];   //_str[pos]在堆上，可用引用返回，支持修改
		}

		const char& operator[](size_t pos) const
		{
			assert(pos < _size);
			return _str[pos];   
		}

		void resize(size_t n, char ch = '\0')
		{
			if (n < _size)
			{
				_str[n] = '\0';
				_size = n;
			}
			else
			{
				reserve(n);
				for (size_t i = _size; i < n; i++)
				{
					_str[i] = ch;
				}
				_str[n] = '\0';
				_size = n;
			}
		}

		void reserve(size_t n)
		{
			if (n > _capacity)
			{
				char* tmp = new char[n+1];
				strcpy(tmp, _str);
				delete[] _str;
				_str = tmp;
				
				_capacity = n;
			}

		}

		void push_back(char ch)
		{
	/*		if (_size == _capacity)
			{
				reserve(_capacity == 0 ? 4 : 2 * _capacity);
			}
			_str[_size] = ch;
			++_size;
			_str[_size] = '\0';*/
			insert(_size, ch);
		}

		void append(const char* str)
		{
	/*		size_t len = strlen(str);
			if (_size + len > _capacity)
			{
				reserve(_size + len);
			}
			strcpy(_str + _size, str);
			_size += len;*/
			insert(_size, str);

		}

		string& operator+=(char ch)
		{
			push_back(ch);
			return *this;
		}

		string& operator+=(const char* str)
		{ 
			append(str);
			return *this;
		}

		void insert(size_t pos, char ch)
		{
			assert(pos <= _size);
			if (_size == _capacity)
			{
				reserve(_capacity == 0 ? 4 : 2 * _capacity);
			}

			//第一种写法
			/*int end = _size;
			while (end >= (int) pos)  //需要强转，pos是size_t类型，end是int，end会被转成size_t类型，即范围小会转向范围大的。
			{						  //当pos等于0，即头插时。结束条件为end小于0，如果不强转，当end小于0时，又会被转成无符号的
				_str[end + 1] = _str[end];  //就会死循环
				--end;
			}*/

			//第二种
			size_t end = _size+1;
			while (end > pos)
			{
				_str[end] = _str[end-1];
				--end;
			}
			_str[pos] = ch;
			++_size;
		}

		void insert(size_t pos, const char* str)
		{
			assert(pos <= _size);
			size_t len = strlen(str);
			if (_size + len > _capacity)
			{
				reserve(_size + len);
			}

			size_t end = _size + len;
			while (end > pos + len - 1)
			{
				_str[end] = _str[end - len];
				end--;
			}
			strncpy(_str + pos, str, len);
			_size += len;
		}

		void erase(size_t pos, size_t len = npos)
		{
			assert(pos < _size);
			if (len == npos || len >= _size - pos)  //len +pos>= _size  不能这么写，会有溢出风险
			{
				_str[pos] = '\0';
				_size = pos;
			}
			else
			{
				strcpy(_str + pos, _str + pos + len);
				_size -= len;
			}
		}

		void swap(string& s)
		{
			std::swap(_str, s._str);
			std::swap(_size, s._size);
			std::swap(_capacity, s._capacity);
		}

		size_t find(char ch, size_t pos = 0) const
		{
			assert(pos < _size);
			for (size_t i = pos; i < _size; i++)
			{
				if (_str[i] == ch)
					return i;
			}
			return npos;
		}

		size_t find(const char* sub, size_t pos = 0) const
		{
			assert(pos < _size);

			const char* p = strstr(_str+pos, sub);
			if (p)
			{
				return p - _str;
			}
			else
			{
				return npos;
			} 
		}

		string substr(size_t pos = 0, size_t len = npos)
		{
			string sub;
			if (len >= _size - pos)
			{
				for (size_t i = pos; i < _size; i++)
				{
					sub += _str[i];
				}
			}
			else
			{
				for (size_t i = pos; i < pos+len; i++)
				{
					sub += _str[i];
				}
			}
			return sub; 
		}

		void clear()
		{
			_size = 0;
			_str[_size] = '\0';
		}

	private:
		char* _str=nullptr;
		size_t _size=0;
		size_t _capacity=0;
	public:
		static const int npos;
	};

	const int string::npos = -1;

	void swap(string& x, string& y)
	{
		x.swap(y);
	} 

	bool operator==(const string& s1, const string& s2)
	{
		int ret = strcmp(s1.c_str(), s2.c_str());
		return ret == 0;
	}

	bool operator<(const string& s1, const string& s2)
	{
		int ret = strcmp(s1.c_str(), s2.c_str());
		return ret < 0;
	}

	bool operator<=(const string& s1, const string& s2)
	{
		return s1 < s2 || s1 == s1;
	}

	bool operator>(const string& s1, const string& s2)
	{
		return !(s1 <= s2);
	}

	bool operator>=(const string& s1, const string& s2)
	{
		return !(s1 < s2);
	}

	bool operator!=(const string& s1, const string& s2)
	{
		return !(s1 == s2);
	}

	ostream& operator<<(ostream& out, const string& s)
	{
		for (auto ch : s)
		{
			out << ch;
		}
		return out;
	}

	istream& operator>>(istream& in, string& s) 
	{
		s.clear(); 
		char ch;
		//in >> ch; 错误，C++规定 cin,scanf默认空格和换行是分隔符，
		ch = in.get();//不会取到,get才能取到
		char buff[128];
		size_t i = 0;
		while (ch != ' ' && ch != '\n')
		{
			buff[i++] = ch;
			if (i == 127)
			{
				buff[127] = '\0';
				s += buff;
				i = 0;
			}
			ch = in.get();
		}
		if (i > 0)
		{
			buff[i] = '\0';
			s += buff; 
		}
		return in;
	}


	istream& getline(istream& in, string& s)
	{
		s.clear();
		char ch;
		//in >> ch; 错误，C++规定 cin,scanf默认空格和换行是分隔符，
		ch = in.get();//不会取到,get才能取到
		while (ch != '\n')
		{
			s += ch;
			ch = in.get();
		}
		return in;
	}

	void test_string1()
	{
		string s1("hello world");
		string s2;

		for (size_t i = 0; i < s1.size(); i++)
		{
			s1[i]++;
		}
		cout << endl;

		for (size_t i = 0; i < s1.size(); i++)
		{
			cout << s1[i] << "";
		}
		cout << endl;

		const string s3("xxxx");
		for (size_t i = 0; i < s3.size(); i++)
		{
			//s3[i]++      错误，可读，但不能写
			cout << s3[i] << "";
		}
		cout << endl;
	}

	void test_string2()
	{
		string s3("hello world");
		string::iterator it3 = s3.begin();
		while (it3 != s3.end())
		{
			//*it3 -= 3;
			cout << *it3 << " ";
			++it3;
		}
		cout << endl;

		for (auto ch : s3)
		{
			cout << ch << " ";
		}
		cout << endl;

		const string s2("hello world");
		string::const_iterator it2 = s2.begin(); 
		while (it2 != s2.end())
		{
			cout << *it2 << " ";
			++it2;
		}
		cout << endl;
	}

	void test_string3()
	{
		string s3("hello world"); 
		s3.push_back('1'); 
		s3.push_back('2');  

		cout << s3.c_str()<< endl; 

		s3 += 'x';  
		s3 += "yyyy"; 
		cout << s3.c_str() << endl; 

		string s1("hello world");
		s1.insert(11, 'x');
		cout << s1.c_str() << endl;

		s1.insert(0, 'x');
		cout << s1.c_str() << endl;
	}

	void test_string4()
	{
		string s1("hello world");
		cout << s1.c_str() << endl;
		
		s1.erase(6, 3);
		cout << s1.c_str() << endl;

		string s2("hello world");
		cout << s2.c_str() << endl;

		s2.resize(5);
		cout << s2.c_str() << endl;

		s2.resize(20, 'x');
		cout << s2.c_str() << endl;

	}


	void test_string5()
	{
		string s1("hello world");
		cout << s1.c_str() << endl;

		string s2(s1);
		cout << s2.c_str() << endl;
		
		string s3("xxxxx");
		s1 = s3;
		cout << s1.c_str() << endl;
		cout << s3.c_str() << endl;
	}

	void test_string6()
	{
		string s1("hello world");
		cout << s1.c_str() << endl;

		s1.insert(6, "xxxx");
		cout << s1.c_str() << endl;

		string s2("xxxxxx");

		cout << s1.c_str() << endl;
		cout << s2.c_str() << endl;
		//swap(s1, s2);  有了全局的swap，就会先调用全局的，
		s1.swap(s2);     //而不是算法库里面的模板swap
		cout << s1.c_str() << endl;
		cout << s2.c_str() << endl;
	}

	void test_string7()
	{
		string url1("https://legacy.cplusplus.com/reference/string/string/substr/");
		string url2("https://www.baidu.com/s?ie=utf-8&f=8&rsv_bp=1&rsv_idx=1&tn=baidu&wd=%E5%90%8E%E7%BC%80%20%E8%8B%B1%E6%96%87&fenlei=256&rsv_pq=0xc61b98d100494ef5&rsv_t=b494uh2Bd6SIxMQ1XY4CwB9MZOD%2BaMk5sx8aiT0NAgUczCRAy8jK7PvP5rxt&rqlang=en&rsv_enter=1&rsv_dl=tb&rsv_sug3=23&rsv_sug1=17&rsv_sug7=100&rsv_sug2=0&rsv_btype=i&inputT=7123&rsv_sug4=8008");

		string protocol, domain, uri; 
		size_t i1 = url1.find(':');  
		if (i1 != string::npos) 
		{
			protocol = url1.substr(0, i1 - 0);//左闭右开，减去后就是个数 
			cout << protocol.c_str() << endl; 
		}

		size_t i2 = url1.find('/',i1+3); 
		if (i2 != string::npos)  
		{
			domain = url1.substr(i1+3, i2-(i1+3));//左闭右开，减去后就是个数 
			cout << domain.c_str() << endl; 
			 
			uri = url1.substr(i2 + 1); 
			cout << uri.c_str() << endl; 
		}
	} 

	void test_string8()
	{
		string s1("hello world");
		string s2("hello world");

		cout << (s1 == s2) << endl;

		cout << ("hello world" == s2) << endl;//因为重载成全局的函数，
		cout << (s2 == "hello world") << endl;//单参数构造支持隐式类型转换。

		cout << s1 << endl;
		cout << s2 << endl;

		cin >> s1 >> s2;

		cout << s1 << endl;
		cout << s2 << endl;

		getline(cin, s1);
		cout << s1 << endl;

	}

	void test_string10()
	{
		string s1("hello world");
		string s2(s1);

		cout << s1 << endl;
		cout << s2 << endl;

	}

}

测试代码

#define _CRT_SECURE_NO_WARNINGS
#include<iostream>
#include<string>
using namespace std;

#include"string.h"

int main()
{
	bit::test_string10();

	return 0;
}

版权声明：本文为博主作者：秦jh_原创文章，版权归属原作者，如果侵权，请联系我们删除！

原文链接：https://blog.csdn.net/qinjh_/article/details/136626941

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