"C + +" operator overloading

This is a C + + feature and a basic syntax for C + +, but if you look at operator overloading as a special class method, and the name of the class method is an operator, everything becomes simple.

Here's a simple procedure to illustrate the problem:

Declaring two 3x3 two-dimensional matrices A, B, is actually the Matrix class, which stores data with a private one-dimensional array of length 9. Just when it's printed, it looks like a two-dimensional array.

The implementation of ~a or ~b can directly print a and B, that is, the equivalent of a B print out, this is the monocular operator overload.

Implements A+b, returning another matrix C after the addition.

This means that the effect is as follows:

The code is as follows:

#include <iostream>using namespace Std;class matrix{private:int matrix[9];//uses a one-dimensional array of length 9 to store 3x3 matrices Public:matrix () {//Here is a matrix class to write two different parameters of the construction method, mainly for programming convenience. for (int i=0;i<9;i++) {this->matrix[i]=0;}} Matrix (int m11,int m12,int m13,int m21,int m22,int m23,int m31,int m32,int M33) {//This construction method is clearly written, there are 9 numbers, respectively assigned to the matrix of 11 position, 12 position ... ... this->matrix[0]=m11;this->matrix[1]=m12;this->matrix[2]=m13;this->matrix[3]=m21;this->matrix[4 ]=m22;this->matrix[5]=m33;this->matrix[6]=m31;this->matrix[7]=m32;this->matrix[8]=m33;} void operator ~ () {//overload of Monocular operator ~, Strict here, cannot have formal parameters. for (int i=0;i<9;i++) {if (i%3==0) {Cout<<endl;} cout<<matrix[i]<< "";//There is no master matrix representing the private member matrix of the Matrix class involved in the operation. Not I lazy not write This-&gt,, is originally cannot have this->. The same}cout<<endl;} Matrix operator + (Matrix &b) {///pair of overloads of binocular operator +, here strict requirements for formal parameters can only be one. Represents the matrix class after the operator. Matrix c;for (int i=0;i<9;i++) {c.matrix[i]=matrix[i]+b.matrix[i];//This is not a private member of the Matrix class that indicates the matrix of the host operator, matrix} return c;}}; int main () {Matrix A (1,2,3,4,5,6,7,8,9); MAtrix B (9,8,7,6,5,4,3,2,1);cout<< "matrix A is as follows:";~a;cout<< "Matrix B is as follows:";~b;cout<< "Matrix A, B is added as follows:"; ~ (A+B); return 0;}

After reading the code, the role of operator overloading is obvious, if you want to declare a class printing method, according to the major object-oriented programming language, basically for this class to open a void xx () printing method, and then this XX printing method, the class's private members this->aa,this- >BB is printed out, in the main function call, to a.xx () so that calls can be called.

After loading the ~, you can print directly to the Matrix class. The equivalent of declaring a print method called ~ in The Matrix class, overloading the original operator of the previous/C + +-bit inverse.

After the overloading of the +, the main is the two matrix class in the private members of the operation. Equivalent to declaring a method similar to Addmatrix (Matrix &b) in the Matrix class, with the addition of this->matrix[i] and B.matrix[i], after the main function matrix C=a.addmatrix (b) The meaning of it.

Finally, it is worth noting that operator overloading can only be used for operations between private members in a class and not for direct operation of the standard type of C. For example, I would like to load the ^ into a power operation between two int, which is absolutely not possible. This is the C language rule, not for what. Operator overloading begins with an operation that is used to customize a class directly.

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"C + +" operator overloading