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Substrac Fraction C++

rayjeyz (11)
This is my code, and I don't know what does "this" mean in my code.
I just followed the example to do my assignment, and I would like to know how "this" work.
Please help me. Thank you :)

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// ProgrammingAssignmentEight.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <iostream>
#include <string>

    using namespace std;
//  ====================
    struct Fraction {
        int den;
        int num;

//  ============
    void SetNum( ) {

        cout << "Please enter an integer value for num: ";
        cin >> num;

    } // Function SetNum
//  ====================

//  ===============
    void SetDen( ){

        cout << "Please enter an integer value for den: ";
        cin >> den;

    } // Function SetDen
//  ====================

//  ==============================
    void Print( string varName ) {
        cout << varName << " = " << num << "/" << den << endl;

    } // Function Print
//  ===================

//  ========================================
    void Subtract( Fraction u, Fraction v ) {

        int a, b, c, d;
        Fraction w;

        a = u.num;
        b = u.den;
        c = v.num;
        d = v.den;

        w.num = a*d - b*c;
        w.den = b*d;

        this ->num = w.num;
        this ->den = w.den;
    } // Substract Function
//  =======================


    }; // Structure Fraction

//  ===============
    int main() {

//  =======================================
//  Declare three Variable of type Fraction
//  =======================================
        Fraction x;
        Fraction y;
        Fraction z;
//  ===============
        x.SetNum();
        x.SetDen();
        x.Print("x");

        y.SetNum();
        y.SetDen();
        y.Print("y");

        z.Subtract(x,y);
        z.Print("z");
        




        return 0;
    } // Function Main
Moschops (7244)
In C++, every class has an implicit pointer to itself. The pointer is named "this". There are practical uses of it. The case above is not a good use of it. You can simply remove the

this ->
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