How were you suposed to use the "cin" operator?

Answer 1

cin in c++, is quite just the opposite of cout. Instead of giving away output, you're getting input. Using cin, it prompts the user to put in input, and waits till the user hits Enter. Let's say for example:
int num;
cin >> num;
Now num contains whatever the user inserted.
CIN equals Console Input, and COUT equals Console Output

Answer 2

Please first review your question. What is Cow here.