要为const矩阵重载“+”运算符,我使用“[]”
Matrix const operator+(const Matrix & mat1, const Matrix & mat2)
{
Matrix sum(mat1);
if (sum.height != mat2.height || sum.width != mat2.width)
cout << "Dimension error!";
else {
for (int i = 0; i < sum.height; i++)
for (int j = 0; j < sum.width; j++)
sum[i][j] = mat2[i][j];
}
return sum;
}
所以,我为[]
定义了重载(const int*)& operator[] (int i) const {
return (*this).ele[i + 1];
}
但IDE会报告错误
"Error IntelliSense: a reference of type "const int *&" (not const-qualified) cannot be initialized with a value of type "int *"
如何解决此错误?我曾多次尝试过TAT。
这就是整个代码:
#define NULL 0
#include<iostream>
using namespace std;
class Matrix {
private:
int width, height;
int **ele;
public:
Matrix();
Matrix(int**);
Matrix(int, int);
Matrix(const Matrix&);
Matrix operator= (const Matrix&);
friend const Matrix operator+ (const Matrix&, const Matrix&);
friend const Matrix operator- (const Matrix&, const Matrix&);
(int*)& operator[] (int i) {
return (*this).ele[i + 1];
}
(const int*)& operator[] (int i) const {
return (*this).ele[i + 1];
}
};
Matrix::Matrix() {
width = 0; height = 0;
ele = NULL;
}
Matrix::Matrix(const Matrix& mat) {
Matrix(mat.height, mat.width);
for (int i = 0; i < height; i++)
for (int j = 0; j < width; j++) {
(*this)[i][j] = mat[i][j];
}
}
Matrix::Matrix(int** e) {
(*this).height = e[0][0];
(*this).width = e[0][1];
for (int i = 1; i < height; i++)
for (int j = 0; j < width; j++) {
(*this).ele[i][j] = e[i][j];
}
}
Matrix::Matrix(int height, int width) {
(*this).width = width;
(*this).height = height;
ele = new int*[height + 1];
ele[0] = new int[2];
ele[0][0] = height; ele[0][1] = width;
for (int i = 1; i < height + 1; i++)
{
ele[i] = new int[width];
}
for (int i = 1; i < height; i++)
for (int j = 0; j < width; j++) {
ele[i][j] = 0;
}
}
inline Matrix Matrix::operator=(const Matrix & mat)
{
Matrix tempMat(mat);
return tempMat;
}
Matrix const operator+(const Matrix & mat1, const Matrix & mat2)
{
Matrix sum(mat1);
if (sum.height != mat2.height || sum.width != mat2.width)
cout << "Dimension error!";
else {
for (int i = 0; i < sum.height; i++)
for (int j = 0; j < sum.width; j++)
sum[i][j] = mat2[i][j];
}
return sum;
}
Matrix const operator-(const Matrix & mat1, const Matrix & mat2)
{
Matrix diff(mat1);
if (diff.height != mat2.height || diff.width != mat2.width)
cout << "Demension error!";
else {
for (int i = 0; i < diff.height; i++)
for (int j = 0; j < diff.width; j++)
diff[i][j] = mat2[i][j];
}
return diff;
}
答案 0 :(得分:0)
我发现你的代码已被编译(g ++版本4.6.3),当从重载的运算符签名中删除括号时,就像用户remyabel所说的那样。 所以试试
int* operator[] (int i) {
return (*this).ele[i + 1];
}
const int* operator[] (int i) const {
return (*this).ele[i + 1];
}
而不是
(int*)& operator[] (int i) {
return (*this).ele[i + 1];
}
(const int*)& operator[] (int i) const {
return (*this).ele[i + 1];
}