this keyword in cpp

1#include <iostream>
2class Entity
3{
4public:
5	int x, y;
6	Entity(int x, int y)
7	{
8		Entity*const e = this;// is a ptr to the the new instance of class 
9		//inside non const method this == Entity*const
10		//e->x = 5;
11		//e->y =6;
12		this->x = x;
13		this->y = x;
14	}
15	int GetX()const
16	{
17		const Entity* e = this;//inside const function this is = const Entity*
18	}
19};
20
21int main()
22
23{
24	Entity e1(1,2);
25}

1 this is a keyword that refers to the current instance of the class. 
2 There can be 3 main usage of this keyword in C++. It can be used to 
3 pass current object as a parameter to another method. 
4 It can be used to refer current class instance variable.
5   
6#include <iostream>
7using namespace std;
8class Demo {
9private:
10  int num;
11  char ch;
12public:
13  void setMyValues(int num, char ch){
14    this->num =num;
15    this->ch=ch;
16  }
17  void displayMyValues(){
18    cout<<num<<endl;
19    cout<<ch;
20  }
21};
22int main(){
23  Demo obj;
24  obj.setMyValues(100, 'A');
25  obj.displayMyValues();
26  return 0;
27}
28
29Output:- 
30  	100
31	A