Don't understand the answer

Question

The question of the challenge was :
"What is the output of this code ?
int x = 3;
int *y = 4;
y = &x;
cout << *y;"

The answer is "error".
I don't see the line which cause the error, even if the line 2 is ambiguous because it assign to y the address 4 (if I understand well).
Why this code output an error ?

Thanks for constructive answers.

Answer 1

It is because of line "int *y = 4;". It is invalid conversion from int to int*. A value cannot be assigned to a pointer this way. It doesn't assign to y addres 4 as you thought. To take an adress of something, operator & have to be used. Pointers are little tricky, so when you finish the challenge and if you are not sure about the answer, write that code and run it. It is the best way to see what happens and what is the mistake, then try to correct it, play with codes.

Answer 2

Problem is a memory - int *y = 4;
Pointer (*) It's a dynamic memory

Do it like this

int x = 3;
int *y = new int(4);
y = &x;
cout << *y;