C++ this pointer

Question 1

Which of the following is true about this pointer?

• It is passed as a hidden argument to all function calls
• It is passed as a hidden argument to all non-static function calls
• It is passed as a hidden argument to all static functions
• None of the above

Question 2

What is the use of this pointer?

• When local variable’s name is same as member’s name, we can access member using this pointer.
• To return reference to the calling object
• Can be used for chained function calls on an object
• All of the above

Question 3

Predict the output of following C++ program.

C

#include<iostream>
using namespace std;

class Test
{
private:
  int x;
public:
  Test(int x = 0) { this->x = x; }
  void change(Test *t) { this = t; }
  void print() { cout << \"x = \" << x << endl; }
};

int main()
{
  Test obj(5);
  Test *ptr = new Test (10);
  obj.change(ptr);
  obj.print();
  return 0;
}

• x = 5
• x = 10
• Compiler Error
• Runtime Error

Question 4

Predict the output of following C++ program

CPP

#include<iostream>
using namespace std;

class Test
{
private:
  int x;
  int y;
public:
  Test(int x = 0, int y = 0) { this->x = x; this->y = y; }
  static void fun1() { cout << \"Inside fun1()\"; }
  static void fun2() { cout << \"Inside fun2()\"; this->fun1(); }
};

int main()
{
  Test obj;
  obj.fun2();
  return 0;
}

• Inside fun2() Inside fun1()
• Inside fun2()
• Inside fun1() Inside fun2()
• Compiler Error

Question 5

Predict the output of following C++ program?

CPP

#include<iostream>
using namespace std;

class Test
{
private:
  int x;
public:
  Test() {x = 0;}
  void destroy()  { delete this; }
  void print() { cout << \"x = \" << x; }
};

int main()
{
  Test obj;
  obj.destroy();
  obj.print();
  return 0;
}

• x = 0
• undefined behavior
• compiler error