PROGRAMMING:Finding the average of prime numbers in a [10]
Input 10 positive integers into the a array to find the average value of primes in the a array.
###Input format:
Enter 10 positive integers separated by spaces in a row, and only one space can be used between the data.
###Output format:
Directly output the real result with 2 decimal places. There are no additional characters.
###Input example:
```in
1 2 3 4 5 6 7 8 9 0
```
###Output example:
```out
four point two five
```
answer：If there is no answer, please comment
###Input format:
Enter 10 positive integers separated by spaces in a row, and only one space can be used between the data.
###Output format:
Directly output the real result with 2 decimal places. There are no additional characters.
###Input example:
```in
1 2 3 4 5 6 7 8 9 0
```
###Output example:
```out
four point two five
```
answer：If there is no answer, please comment