<分区>
我是 C++ 的初学者，所以我开始通过自己编写一点点练习 Vector类(class)。
它存储数组的行数和列数，元素是动态分配的。
template <class T>
class Vector {
private:
unsigned int rows;
unsigned int cols;
T **elements;
public:
Vector(unsigned int, unsigned int);
~Vector();
};
template <class T>
Vector<T>::Vector(unsigned int rows, unsigned int cols) {
this->rows = rows;
this->cols = cols;
this->elements = new T[this->rows];
for (int i = 0; i < this->rows; i++) {
this->elements[i] = new T[this->cols];
}
}
template <class T>
Vector<T>::~Vector() {
};
这是代码。当我编译它时(我创建一个对象来测试它:Vector<int> test;)，我收到错误:"Cannot convert ‘int*’ to ‘int**’ in assignment" .
为什么会出现此错误？我在网上看到了多维动态分配示例:http://www.cplusplus.com/forum/beginner/63/
最大的错误是在分配指针数组时遗漏了'*':
this->elements = new T*[this->rows];
除此之外:
- 为什么要将 vector 定义为具有行和列的矩阵？
- 分配内存并在不再需要时使用内存
- 访问器应该可用
以下面的代码作为起点:
template <class T>
class Vector {
public:
unsigned int rows;
unsigned int cols;
T** elements;
Vector(unsigned int, unsigned int);
~Vector();
};
template <class T>
Vector<T>::Vector(unsigned int rows, unsigned int cols) {
this->rows = rows;
this->cols = cols;
this->elements = new T*[this->rows];
for (int i = 0; i < this->rows; i++) {
this->elements[i] = new T[this->cols];
}
}
template <class T>
Vector<T>::~Vector() {
for(int i=0; i<this->rows;++i)
delete[] this->elements[i];
delete[] this->elements;
};
int main()
{
Vector<int> obj(2,2);
obj.elements[0][0] = 1;
obj.elements[0][1] = 2;
obj.elements[1][0] = 3;
obj.elements[1][1] = 4;
std::cout << obj.elements[0][0] << " " << obj.elements[0][1] << std::endl;
std::cout << obj.elements[1][0] << " " << obj.elements[1][1] << std::endl;
return 0;
}
Example