数据结构（二）collection、OrderedCollection、Rectangle、matrix

1、Collection类模板

代码:

/*
Collection类模板
*/
#include <iostream>
#include <vector>
#include<stdlib.h> 
using namespace std;
template <typename Object>
class Collection
{
private:
 vector<Object> vs;
public:
 Collection()
 {
  vs.reserve(10);
 }
 int Get_Size() const
 {
  return vs.size(); 
 }
 void insert(const Object& temp)
 {
  vs.push_back(temp);
 }
 bool isEmpty() const
 {
  return Get_Size() == 0;
 }
 void makeEmpty() 
 {
  vs.clear();
 }
 void remove(int index) 
 {
  if (isEmpty())
  {
   cout << "Vector is empty, so it can't be removed." << endl;
   exit(1);
  }
  vs.erase(vs.begin() + index);
 }
 Object& operator [](int index)  
 {
  return vs[index];
 }
 const Object& operator [](int index) const  
 {
  return vs[index];
 }
 int contains(const Object& temp)
 {
 	for(int i=0;i<vs.size();i++)
 	{
 		if(temp==vs[i]) 
 		{
 			cout<<"x位于当前序列中"<<endl;
 			return 1;
 		}
		  
 	}
 	cout<<"x不位于当前序列中"<<endl;
 	return 0;
 }
};
int main()
{
 Collection<int> cell;
 cell.insert(2);
 cell.insert(1);
 cell.insert(5);
 cell.insert(10);
 int x;
 cin>>x;
 cell.contains(x);
 cell.makeEmpty();
 cell.remove(0);
 cout << cell.isEmpty() << endl;
return 0;
}

运行:

2、OrderedCollection模板类 

代码:

/*
OrderedCollection模板类 
*/
#include <iostream>
#include <vector>
#include<stdlib.h> 
using namespace std;
template <typename Comparable> 
class OrderedCollection
{
private:
 vector<Comparable> vs;
public:
 OrderedCollection()
 {
  vs.reserve(10);
 }
 int Get_Size() const
 {
  return vs.size(); 
 }
 void insert(const Comparable& temp) 
 {
  vs.push_back(temp);
 }
 bool isEmpty() const
 {
  return Get_Size() == 0;
 }
 void makeEmpty()
 {
  vs.clear();
 }
 void remove(int index)
 {
  if (isEmpty())
  {
   cout << "Vector is empty, so it can't be removed." << endl;
   exit(1);
  }
  vs.erase(vs.begin() + index);
 }
 Comparable& operator [](int index)  
 {
  return vs[index];
 }
 const Comparable& operator [](int index) const  
 {
  return vs[index];
 }
 const Comparable& findMin() const 
 {
  if (isEmpty())
  {
   cout << "Vector is empty, so it can't be compared." << endl;
   exit(1);
  }
  int index = 0;
  for(unsigned int i = 1; i < vs.size(); i++)
  {
   if (vs[i] < vs[index])
   {
    index = i;
   }
  }
  return vs[index];
 }
 const Comparable& findMax() const
 {
  if (isEmpty())
  {
   cerr << "Vector is empty, so it can't be compared." << endl;
   exit(1);
  }
  int index = 0;
  for (unsigned int i = 1; i < vs.size(); i++)
  {
   if (vs[i] > vs[index])
   {
    index = i;
   }
  }
  return vs[index];
 }
};
int main()
{
 OrderedCollection<int> cell;
 cell.insert(2);
 cell.insert(1);
 cell.insert(5);
 cell.insert(10);
 cout << cell.findMin() << endl;
 cout << cell.findMax() << endl;
 cell.makeEmpty();
 cell.remove(0);
 cout << cell.isEmpty() << endl;
 cout << cell.findMax() << endl;
    return 0;
}

运行:

3、使用 Rectangle类

代码：

/*
使用 Rectangle类
*/ 
#include <iostream>
#include <vector>
using namespace std;

/**
* Return the maximum item in array a.
* Assumes a.size( ) > 0.
* Comparable objects must provide operator< and operator=
*/
template <typename Comparable>
const Comparable & findMax(const vector<Comparable> & a)
{
	int maxIndex = 0;
	for (int i = 1; i < a.size(); ++i)
		if (a[maxIndex] < a[i])
			maxIndex = i;
	return a[maxIndex];
}

class Rectangle
{
public:
	explicit Rectangle(double l=0.0,double w=0.0) : length{l},width{w}
	{ }
	double getLength() const
	{
		return length;
	}
	double getWidth() const
	{
		return width;
	}
	double getArea() const
	{
		return length*length;
	}
	double getPerimeter() const
	{
		return 2*(length+width);
	}
	void print(ostream & out = cout) const
	{
		out << "(Rectangle " <<"长"<< getLength()<<","<<"宽"<<getWidth() << ")";
	}
	bool operator< (const Rectangle & rhs) const
	{
		if(getArea()<rhs.getArea()) 
		    return  getArea()<rhs.getArea();
	         else 
			   if(getPerimeter()<getPerimeter())
		         return getPerimeter()<getPerimeter();
		     
		 
	}
private:
	double length,width;
};

// Define an output operator for Rectangle
ostream & operator<< (ostream & out, const Rectangle & rhs)
{
	rhs.print(out);
	return out;
}

int main()
{
	vector<Rectangle>v(3);
		v[0]=Rectangle{ 3.0,2.0 };
		v[1]=Rectangle{ 2.5,2.5 };
		v[2]=Rectangle{ 2.3,2.7 };
	cout << "Largest Rectangle: " << findMax(v) << endl;
	return 0;
}

运行:

4、完善matrix类模板

代码：

/*
完善matrix类模板
*/ 
#include <iostream>
#ifndef MATRIX_H
#define MATRIX_H
#include <vector>
using namespace std;
template <typename Object>
class matrix
{
	public:
		
		//无参构造函数，将array初始化为 2*2的matrix 
		matrix()
		{
			array.resize(2);
			for(vector<Object> & thisRow : array)
				thisRow.resize(2);
		}
		matrix(int rows, int cols) : array(rows)
		{
			for (auto & thisRow : array)
			thisRow.resize(cols);
		}
		matrix(vector<vector <Object> > v) : array{ v }{}
		matrix(vector<vector <Object> > && v) : array{ std::move(v) }{ }
		
		//增加的resize方法 
		void resize(int rows,int cols)
		{
			array.resize(rows);
			for(vector<Object> & thisRow : array)
			{
				thisRow.resize(cols);
			}
		}
		
		const vector<Object> & operator[](int row) const
		{
			return array[row];
		}
		vector<Object> & operator[](int row)
		{
			return array[row];
		}
		int numrows() const
		{
			return array.size();
		}
		int numcols() const
		{
			return numrows() ? array[0].size() : 0;
		}
	private:
		vector<vector<Object>> array;
};
#endif
int main()
{
	
	matrix<char> a(3,2);
	cout<<a.numrows()<<' '<<a.numcols()<<endl;
	a.resize(4,2);
	cout<<a.numrows()<<' '<<a.numcols()<<endl;
	matrix<int> b;
	cout<<b.numrows()<<' '<<b.numcols()<<endl;
	
	return 0;
}

运行: