PROGRAMMING:Definition class 2

Please add the following code to complete the output requirements（ Note: need to submit full code)

import java.util.Scanner;
public class Main {
public static void main(String[] args) {                            
double dd = RR.fun();
System.out.printf("%.2f",dd);
}
}
class RR{
}

###Input format:
Give five real numbers in a row up to 1000.
###Output format:
Output the number in the middle, keep two decimal places.
###Input example:
```in
1 2 5 4 3
```
###Output example:
```out
five
```






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