string homework

homework02/rudolf/string.cpp

@@ -0,0 +1,73 @@
+#include "string.h"
+
+String::String():
+		mString(nullptr),
+		mSize(0),
+		mCapacity(0)
+{};
+String::String(const char* chars,std::size_t capacity):
+		mString(new char[capacity>strlen(chars)?capacity:strlen(chars)]),
+		mSize(strlen(chars)),
+		mCapacity(capacity>strlen(chars)?capacity:strlen(chars))
+{
+	std::copy_n(chars,mSize,mString.get());
+};
+String String::operator=(String str)
+{
+	std::swap(mString,str.mString);
+	mSize =str.size();
+	mCapacity =str.capacity();
+	return *this;
+}
+String& String::operator+(const String& str)
+{	
+	String str2(c_str(),size()+str.size());
+	for(std::size_t i=0;i<str.mSize; i++) 
+	{		
+		str2.push_back(str.mString[i]);
+	}
+	*this=str2;
+	return *this;
+}
+void String::push_back(const char c)
+{
+	if (mSize==mCapacity)
+		{add_capacity();}
+	mString[mSize] = c;
+	mSize+=1;
+}
+void String::add_capacity()
+{
+	std::unique_ptr<char[]> newString(new char[mCapacity*2 + 1]);
+	std::copy_n(mString.get(),mSize,newString.get());
+	mString=std::move(newString);
+}
+
+std::size_t strlen(const char* chars)
+{
+	std::size_t counter(0);
+	while(chars[counter]){++counter;}
+	return counter;
+}
+
+bool operator==(const std::string& str1,const String& str2)
+{
+	return str1==std::string(str2);
+}
+
+bool operator==(const char* chars,const String& str)
+{
+	return String(chars)==str;
+};
+
+String operator+(const char* chars, const String& str)
+{
+	return String(chars)+str;
+}
+
+std::ostream& operator<<(std::ostream& os, const String& string)
+{
+	return  os << string.c_str();
+};
+
+

homework02/rudolf/string.h

@@ -0,0 +1,51 @@
+#pragma once
+#include <iostream>
+#include <memory>
+#include <algorithm>
+
+std::size_t strlen(const char* chars);
+
+class String
+{
+public:
+	String();
+
+	String(const char* chars,std::size_t capacity);
+
+	String(const char* chars):String(chars,strlen(chars)){};
+
+	String(const String& str):String(str.c_str()){};
+
+	String operator=(String str);
+
+	const bool empty()const {return mSize==0;}
+
+	char& operator[](int idx)const { return mString[idx];}
+
+	bool operator==(const String& str)const{return std::equal(c_str() , c_str() + mSize , str.c_str());};
+
+	String& operator+(const String& str);
+
+	operator std::string()const{return c_str();}
+
+	void push_back(const char c);
+	void add_capacity();
+
+	std::size_t size()const{return mSize;};
+	std::size_t capacity()const{return mCapacity;};
+
+	const char* c_str()const {return mString.get();}
+private:
+	std::unique_ptr<char[]> mString;
+	std::size_t mSize;
+	std::size_t mCapacity;
+};
+
+
+bool operator==(const std::string& str1,const String& str2);
+
+bool operator==(const char* chars,const String& str);
+
+String operator+(const char* , const String& str);
+
+std::ostream& operator<<(std::ostream&, const String&);