第二个头文件Array2D.h是二维动态数组类模板：
//Array2D.h
#ifndef CARL_SEN_ARRAY2D_H
#define CARL_SEN_ARRAY2D_H
#include "Array.h"
#include <iostream>
#include <cstdarg>
using std::ostream;
using std::out_of_range;
template <typename T>
class Array2D {
protected:
unsigned int rows;
unsigned int cols;
Array<T> array;
public:
//构造函数
Array2D(unsigned int _rows=0, unsigned int _cols=0);
Array2D(unsigned int _rows, unsigned int _cols, T data1, ...);
//两种重载运算符
class RowArray;
RowArray operator[](unsigned int row);
const RowArray operator[](unsigned int row) const;
friend ostream& operator<<(ostream& os, const Array2D<T>& array2D);
//计算第二维下标操作的嵌套类
class RowArray {
private:
const Array2D<T>& array2D;
unsigned int row;
public:
RowArray(Array2D<T>& _array2D, unsigned int _row=0):
array2D(_array2D), row(_row) {}
RowArray(const Array2D<T>& _array2D, unsigned int _row=0):
array2D(_array2D), row(_row) {}
T& operator[](unsigned int col) {
if(col>=array2D.cols) {
throw out_of_range("invalid col");
}
return const_cast<Array2D<T>&>(array2D).array[row*array2D.cols+col];
}
const T& operator[](unsigned int col) const {
if(col>=array2D.cols) {
throw out_of_range("invalid col");
}
return array2D.array[row*array2D.cols+col];
}
};
friend class RowArray;
//get，set函数
unsigned int getRows() const {
return rows;
}
unsigned int getCols() const {
return cols;
}
};
template <typename T>
Array2D<T>::Array2D(unsigned int _rows, unsigned int _cols):
rows(_rows), cols(_cols), array(_rows*_cols){
for(unsigned int i=0; i<rows*cols; ++i) {
array[i]=T();
}
}
template <typename T>
Array2D<T>::Array2D(unsigned int _rows, unsigned int _cols, T data1, ...):
rows(_rows), cols(_cols),array(_rows*_cols){
va_list ap;
va_start(ap, _cols);
for(unsigned int i=0; i<rows*cols; ++i) {
array[i]=va_arg(ap, T);
}
va_end(ap);
}
template <typename T>
Array2D<T>::RowArray Array2D<T>::operator[](unsigned int row) {
if(row>=rows) {
throw out_of_range("invalid row");
}
return RowArray(*this, row);
}
template <typename T>
const Array2D<T>::RowArray Array2D<T>::operator[](unsigned int row) const {
if(row>=rows) {
throw out_of_range("invalid row");
}
return RowArray(*this, row);
}
template <typename T>
ostream& operator<<(ostream& os, const Array2D<T>& array2D) {
unsigned int i, j;
for(i=0; i<array2D.rows; ++i) {
for(j=0; j<array2D.cols; ++j) {
os<<array2D.array[i*array2D.cols+j]<<"\t";
}
if(i!=array2D.rows-1) {
os<<endl;
}
}
return os;
}
#endif
现在就可以使用它们了，如下面的测试程序：
#include "Array.h"
#include "Array2D.h"
#include <iostream>
#include <string>
using std::string;
using std::cout;
using std::endl;
void testArray();
void testArray2D();
int main() {
testArray();
testArray2D();
return EXIT_SUCCESS;
}
void testArray() {
//普通数组
Array<int> a1(3);
cout<<"Testing Array: print 1"<<endl;
cout<<a1<<endl; //整体打印
unsigned int i;
for(i=0; i<a1.getSize(); ++i) {
a1[i]=i+1; //逐个赋值
}
cout<<"Testing Array: print 2"<<endl;
for(i=0; i<a1.getSize(); ++i) {
cout<<a1[i]<<"\t"; //逐个打印
}
cout<<endl;
