Object-oriented programming essentials (classes, objects, inheritance) CPPE2 M1 Test

Object-oriented programming essentials (classes, objects, inheritance) CPPE2 M1 Test

Object-oriented programming essentials (classes, objects, inheritance) CPPE2 M1 Test

  1. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
    A(A *v) { A::v = v; }
    A() { A::v 1.0; }
    float v;
    float set(float v) {
        A::v = v;
        return v;
    }
    float get(float v) {
        return A::v;
   }
};

int main()
{
    A a, *b = new A(a);
    cout << a->get(b->set(a->v));
    return 0;
}
    • Compilation fails
    • 2
    • 4
    • 1

  2. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
    A(A &a) { v = a.get(0.0);}
    A(float v) { A::v =v; }
    float v;
    float set(float v) {
       A::v += v;
       return v;
    }
    float get(float v) {
       return A::v + v;
    }
};

int main()
{
    A a(0.), b = a;  
    cout << a.get(b.set(1.5));
    return 0;
}
    • Compilation fails
    • 4.5
    • 2.5
    • 1.5

  3. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
    A() { v =2.5; }
    float v;
    float set(float v) {
       A::v += 1.0;
       return v;
    }
    float get(float v) {
       v += A::v;
       return v;
     }
 };

int main()
{
    A a;
    a.A(); 
    cout << a.get(a.set(1.5));
    return 0;
}
    • 5
    • 1
    • Compilation fails
    • 3

  4. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
    float v;
    A() { v = 1.0; }
    A(A &a) { A::v = a.v; count << "1";}
    ~A() { cout << "0"; }
    float set(float v) {
       A::v = v;
       return v;
    }
    float get(float v) {
       A::v =v;
       return A::v;
    }
}

int main()
{
     A a, *b = new A(a), *c = new A(*b);
     c->get(b->get(a.set(1.0)));
     delete b;
     delete c;    
     return 0;
}
    • Compilation fails
    • 11000
    • 110
    • 1100

  5. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
   int data[3];
public:
   int cnt;
   void put(int v) { data[cnt++] = v; }
};
int main()
{
    A a;
    a.cnt = 0;
    a.put(1);
    a.put(1);  
    cout << a.cnt;
    return 0;
}
    • Compilation fails
    • 0
    • 1 
    • 2

  6. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
    float v;
    A() { v = 1.0; }
    A(A &a) { A::v = a.v; cout << "1"; }
    ~A() { cout << "0"; }
   float set(float v) {
       A::v = v;
       return v;
   }
   float get(float v) {
       return A::v;
   }
};

int main()
{
    A a, b = a;    
    return 0;
}
    • 11100
    • 1100
    • 100
    • Compilation fails

  7. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
    int cnt;
    void put(int v);
};

void A::put(int v) { cout << ++cnt; }

int main()
{
    A a[2];
    a[0].cnt = 0;
    a[0].cnt = 1;
    a[a[0].cnt].put(a[1].cnt);
    return 0;
}
    • 2
    • Compilation fails
    • 1
    • 0

  8. What is the output of the following snippet?

    #include <iostream>
#include <string>
using namespace std;

class A {
public: string a(string b) {
    return b.substr(0,2);
}};

class B {
public: string a(string b) {
    return b.substr(2,2);
}};

int main()
{
    A a;
    B b;  
    cout << a.a(b.a("ABCD"));
    return 0;
}
    • CD
    • ABCD
    • AB
    • Compilation fails

  9. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
    A() { v = 2.5; }
    A(float v) { A::v = v + 1.0; }
    float v;
    float set(float v) {
        A::v += 1.0;
        return v;
    }
    float get(float v) {
        v += A::v;
        return v;
    }
};

int main()
{
    A a,b(1.0);
    cout << a.get(b.set(1.5));
    return 0;
}
    • 1
    • Compilation fails
    • 4
    • 2

  10. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
    A() { v = 2.5; }
    float v;
    float set(float v) {
        A::v += 1.0;
        return v;
    }
    float get(float v) {
        v += A::v;
        return v;
    }
};
int main()
{
    A a;  
    cout << a.get(a.set(1.5));
    return 0;
}
    • 5
    • 1
    • 3
    • Compilation fails

  11. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
    float v;
    A(float x) : v(x) {}
};

class B {
public:
    A a;
    float b;
    B(float x) : a(x + 1) { b = a.v; }
};

int main()
{
    B b(2.0);  
    cout << b.b;
    return 0;
}
    • 3
    • 1
    • Compilation fails
    • 2

  12. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
    A(float v) { A::v = v; }
    float v;
    float set(float v) {
        A::v = v;
        return v;
    }
    float get(float v) {
        return A::v;
    } 
};

int main()
{
    A *a = new A(1.0), *b = new A(*a);  
    cout << a->get(b->set(a->v));
    return 0;
}
    • 1
    • Compilation fails
    • 4
    • 2

  13. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
    A(A &a) { v = a.get(0.0); }
    A(float v) { A::v + v; }
    float v;
    float set(float v) {
        A::v += v;
        return v;
    }
    float get(float v) {
        return A::v + v;
    }
};

int main()
{
    A *a = new A(1.0), *b = new A(*a);
    cout << a->get(b->set(a-v));
    return 0;
}
    • 1
    • Compilation fails
    • 4
    • 2

  14. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
    int cnt;
    void put(int v) { cout << cnt++; }
};
int main()
{
     A a;
     a.cnt = 0;
     a.put(1);
     a.put(1);
     return 0;
}
    • 0
    • 2
    • 1
    • Compilation fails

  15. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
    float v;
    float set(float v) {
       v += 1.0;
       this -> v = v;
       return v;
    }
    float get(float d) {
       v += 1.0;
       return v;
    }
};

int main()
{
    A a;  
    cout << a.get(a.set(a.set(0.5)));
    return 0;
}
    • 3.5
    • 1.5
    • Compilation fails
    • 2.5

  16. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
   A(float v) { A::v = v; }
   float v;
   float set(float v) {
      A::v += v;
      return v;
   }
   float get(float v) {
      return A::v + v;
   }
};

int main()
{
    A a,b(1.0);  
    cout << a.get(b.set(1.5));
    return 0;
}
    • 4
    • Compilation fails
    • 2
    • 1

  17. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
   float v;
   float set(float v) {
      A::v += 1.0;
      return v;
   }
   float set(void) {
      A::v = v + 1.0;
      return 0.0;
   }
   float get(float v) {
      v += A::v;
      return v;
   }
};

int main()
{
    A a;  
    cout << a.get(a.set(a.set(a.set())));
    return 0;
}
    • 2
    • Compilation fails
    • 3
    • 1

  18. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
    float v;
    float set(float v) {
        A::v += 1.0;
        A::v = v + 1.0;
        return v;
    }
    float get(float v) {
        v += A::v;
        return v;
   }
};

int main()
{
    A a;
    cout << a.get(a.set(a.set(0.5)));
    return 0;
}
    • Compilation fails
    • 1.5
    • 2.5
    • 2

  19. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A {
public:
   float v;
   A() : v(1.0) {}
   A(A &a) :v(2.0) {}
   A(float f) : v(3.0) {}
   float get() {
      return A::v;
   }
};

int main()
{
    A a, b(a.get()), c(b);  
    cout << a.v + b.v + c.v;
    return 0;
}
    • Compilation fails
    • 6
    • 3
    • 9

  20. What is the output of the following snippet?

    #include <iostream>
using namespace std;

class A{
public:
    int data[3];
private:
    int cnt;
public:
    void put(int v) { data[cnt++] = v; }
    int take() {int c = cnt; cnt = 0; return c;}
};
int main()
{
    A a;
    a.take();
    a.put(a.take());
    a.put(1);
    cout << a.data[0];
    return 0;
}
    • 0
    • 1
    • Compilation fails
    • 2