指针将随机打印它的地址，而不是它的指针值，C ++ [英] Pointer will randomly print it's address instead of it's pointed value, C++

问题描述

所以我有这个问题，其中的输出打印我的指针的地址，我不知道为什么这会发生cuz的指针是不会修改

So I have this problem where the output prints the address of my pointer, I have no idea why this happens cuz the pointers is not modified at all

代码：

using namespace std;

class AndroideAbstracto {
protected:
    int *vida;
    int *fuerza;
    int *velocidad;
public:

    void setvalores(int vi, int fu, int ve) {
        velocidad = &ve;
        vida = &vi;
        fuerza = &fu;

    };
    virtual void imprimir(void) = 0;
};

class Androide : public AndroideAbstracto {
public:

    void imprimir() {
        std::cout << "Caracteristicas del androide:" << endl;
        cout << "Velocidad = " << *velocidad << endl;
        cout << "Vida = " << *vida << endl;
        cout << "Fuerza = " << *fuerza << endl;

    };

};

class Decorator : public AndroideAbstracto {
protected:
    AndroideAbstracto *AndroideDec;
public:

    Decorator(AndroideAbstracto* android_abs) {
        AndroideDec = android_abs;
    }
    virtual void imprimir(void) = 0;
};

class Androide_Con_Habi : public Decorator {
protected:
    string habilidad;
public:

    Androide_Con_Habi(AndroideAbstracto* android_abs, string habi) : Decorator(android_abs) {
        habilidad = habi;
    }

    virtual void imprimir() {
        AndroideDec->imprimir();
        cout << "La habilidad especial del androide es: " << habilidad << endl;
    }
};

class Androide_Elegido : public Decorator {
protected:
    bool elegido;
public:

    Androide_Elegido(AndroideAbstracto *android_abs, bool es) : Decorator(android_abs) {
        elegido = es;
    }

    virtual void imprimir() {
        if (elegido) {
            //            *vida =(*vida) * 2;  //Im quite new to C++ so im not really
            //            *fuerza *=2;         //sure how should I multiply these pointers
            //            *velocidad *=2;
            //            AndroideDec->setvalores(vida*2,fuerza*2,velocidad*2);
            AndroideDec->imprimir();
            cout << "Este androide es uno de los elegidos";
        }
    }
};

int main(int argc, char *argv[]) {

    Androide *andro = new Androide();
    andro->setvalores(600, 700, 300);
    andro->imprimir();
    Androide_Con_Habi *andro_con_habi = new Androide_Con_Habi(andro, "Volar");
    andro_con_habi->imprimir();

    Androide_Elegido *superpoderoso = new Androide_Elegido(andro, true);
    superpoderoso->imprimir();

    delete superpoderoso;
    delete andro;
    delete andro_con_habi;
    return 0;
}

我不知道为什么，但打印：

I have no idea why but this prints:

Caracteristicas del androide:
Velocidad = 300
Vida = 600
Fuerza = 700

Caracteristicas del androide:
Velocidad = 300
Vida = 152436744
Fuerza = -1074718788
La habilidad especial del androide es: Volar


Caracteristicas del androide:
Velocidad = 300
Vida = 152436744
Fuerza = 1
Este androide es uno de los elegidos 

推荐答案

void setvalores(int vi, int fu, int ve) {
    velocidad = &ve;
    vida = &vi;
    fuerza = &fu;

};

指向 vi ， fu 和 ve 在函数返回时无效。你没有看到地址被打印，而只是垃圾。

The pointers to vi, fu, and ve get invalidated when the function returns. You're not seeing addresses being printed, but simply garbage.

你的整个设计不，也不应该使用指针。

Your entire design doesn't and shouldn't need to use pointers though.

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