Question about pointer and reference outputs

Question

Why is the output to the following code 1021 and not 1121?

int x= 10, y= 20;
int *ptr = &x;
int &ref = y;
*ptr++;
ref++;
cout<<x<<y;

Answer 1

No, it was not right. It is due to operators priority. ptr is increased before reading.
Try (*ptr)++.

Answer 2

Philip I wasn't right and corrected my answer.

Answer 3

Thank you, Sergey Ushakov!

Answer 4

Tind 😉