//001 IntCell类的完整声明
class IntCell
{
private:
int storedValue;
public:
IntCell(){storedValue = 0;}
IntCell(int initialValue){storedValue = initialValue;}
int read(){return storedValue;}
void write(int x){storedValue = x;}
};
//002 改进的IntCell类
class IntCell
{
private:
int storedValue;
public:
explicit IntCell(int initialValue = 0):storedValue(initialValue){}
int read() const {return storedValue;}
int write(int x){storedValue = x;}
};
//003 接口与实现的分离 three files
//IntCell.h
#ifndef IntCell_H
#define IntCell_H
class IntCell
{
private:
int storedValue;
public:
explicit IntCell(int initialValue = 0);
int Cellread() const;
void write(int x);
};
#endif
//IntCell.cpp
#include "IntCell.h"
IntCell::IntCell(int initialValue):storedValue(initialValue){}
int IntCell::read() const {return storedValue;}
void IntCell:: write(int x){storedValue = x;}
//TestIntCell.cpp
#include <iostream>
#include "IntCell.h"
using namespace std;
int main()
{
IntCell m;
m.write(5);
cout << "Cell contents: " << m.read() << endl;
return 0;
}
//004 vector类的例子
#include <iostream>
#include <vector>
using namespace std;
int main()
{
vector<int> squares(100);
for (int i = 0; i < squares.size(); i++)
squares[i] = i*i;
for (int i = 0; i < squares.size(); i++)
cout << i << " " << squares[i] << endl;
return 0;
}
//005 003中IntCell类的指针用法
int main()
{
IntCell *m;
m = new IntCell;
m->write(5);
cout << "Cell Contents: " << m->read() << endl;
delete m;
return 0;
}
//006 数据成员是指针的IntCell类实现
//IntCell.h
#ifndef IntCell_H
#define IntCell_H
class IntCell
{
private:
int * storedValue;
public:
explicit IntCell(int initialValue = 0);
IntCell(const IntCell & rhs);
~IntCell();
const IntCell& operator=(const IntCell & rhs);
int read() const;
void write();
}；
#endif
//IntCell.cpp
#include "IntCell.h"
IntCell::IntCell(int initialValue = 0)
{
storedValue = new int(initialValue);
}
IntCell::IntCell(const IntCell& rhs)
{
storedValue = new int(*rhs.storedValue);
}
IntCell::~IntCell()
{
delete storedValue;
}
const IntCell& IntCell::operator=(const IntCell& rhs)
{
if (this != &rhs)
*storedValue = *rhs.storedValue;
return *this;
}
int IntCell::read() const
{
return *storedValue;
}
void IntCell::write(int x)
{
*storedValue = x;
}
//IntCellTest.cpp
#include <iostream>
#include "IntCell.h"
int main()
{
IntCell a(2);
IntCell b = a;
IntCell c;
c = b;
a.write(4);
cout << a.read() << endl
<< b.read() << endl
<< c.read() << endl;
return 0;
}
//007 未分离的MemoryCell类模板
template <typename Object>
class MemoryCell
{
private:
Object storedValue;
public:
explicit MemoryCell(const Object& initialValue = Object()):storedValue(initialValue){}
const Object& read() const {return storedValue;}
void write(const Object& x) {storedValue = x;}
};
//008 使用MemoryCell类模板的程序
int main()
{
MemoryCell<int> m1;
MemoryCell<string> m2("hello");
m1.write(37);
m2.write(m2.read() + " world");
cout << m1.read() << endl
<< m2.read() << endl;
return 0;
}
//009 泛型函数findMax的例子
class Employee
{
private:
string name;
double salary;
public:
void setValue(const string& n, double s){name = n; salary = s;}
const string& getName() const {return name;}
void print(ostream& out) const {out << name << " (" << salary << ")" ;}
bool operator<(const Employee& rhs) const {return salary < rhs.salary;}
};
ostream& operator<<(ostream& out, const Employee& rhs)
{
print(out);
return out;
}
int main()
{
vector<Employee> v(3);
v[0].setValue("George Bush", 400000.00);
v[1].setValue("Bill Gates", 2000000000.00);
v[2].setValue("Dr. Phil", 13000000.00);
cout << findMax(v) << endl;
return 0;
}
//010 findMax函数模板
/**
* 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];
}
//011 函数对象作为findMax的第二个参数
template <typename Object, typename Comparator>
const Object& findMax(const vector<Object>& arr, Comparator cmp)
{
int maxIndex = 0;
for (int i = 1; i < arr.size(); i++)
if (cmp.isLessThan(arr[maxIndex]), arr[i])
maxIndex = i;
return arr[maxIndex];
}
class CaseInsensitiveCompare
{
public:
bool isLessThan(const string& lhs, const string& rhs) const
{
return stricmp(lhs.c_str(), rhs.c_str()) < 0;
}
};
int main()
{
vector<string> arr[3];
arr[0] = "ZEBAR";
arr[1] = "alligator";
arr[2] = "crocodile";
cout << findMax(arr, CaseInsensitiveCompare()) << endl;
return 0;
}
//012 第二个版本findMax
template <typename Object, typename Comparator>
const Object& findMax(const vectror<Object>& arr, Comparator isLessThan)
{
int maxIndex = 0;
for (int i = 1; i < arr.size(); i++)
if (isLessThan(arr[maxIndex], arr[i]))
maxIndex = i;
return arr[maxIndex];
}
#include <functional>
template <typename Object>
const Object& findMax(const vector<Object>& arr)
{
findMax(arr, less<Object>());
}
class CaseInsensitiveCompare
{
public:
bool operator()(const Object& lhs, const Object& rhs) const
{
return stricmp(lhs.c_str(), rhs.c_str()) < 0;
}
}
int main()
{
vector<string> arr[3];
arr[0] = "ZEBRA";
arr[1] = "alligator";
arr[2] = "crocodile";
cout << findMax(arr, CaseInsensitiveCompare()) << endl;
cout << findMax(arr) << endl;
return 0;
}
//013 矩阵
#ifndef MATRIX_H
#define MATRIX_H
#include <vector>
using namespace std;
template <typename Object>
class matrix
{
private:
vector <vector<Object>> array;
public:
matrix(int rows, int cols):array(rows)
{
for (int i = 0; i < array.size(); i++)
array[i].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;
}
};
