PROGRAMMING:N personal circle, looking for 3 games

There are n people in a circle, in order. Start counting from the first person (counting from 1 to 3)
The people who got to 3 quit the circle and asked what number they were in.
This topic requires reading in the total number of N, according to the rules of the game to find out the number of the last person left.
###Input format:
Total number n
###Output format:
The number of the last person left is num
###Input example:
Here is a set of inputs. For example:
```in
five
```
###Output example:
The corresponding output is given here. For example:
```out
four
```







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Title Requirements:
There are n people in a circle, in order. Start counting from the first person (counting from 1 to 3)
The people who got to 3 quit the circle and asked what number they were in.