PROGRAMMING:Area of a triangle_ one
Input 3 sides of a triangle (a,b,c, all sides are floating numbers), calculating the area of the triangle.
The fomular is: $$area = √(s*(s-a)*(s-b)*(s-c) ) (among which: s=(a+b+c)/2)$$
![ Tim screenshot 20190319145526. PNG] (~ / 658719e7-af42-4e4a-b428-8cd437795f. PNG)
### Input Specification:
Input 3 floating numbers in one line, separate each other by ','.
### Output Specification:
Output the area hold 2 fraction digits
### Sample Input:
```in
4,5,6
```
### Sample Output:
```out
The area is 9.92
```
answer：If there is no answer, please comment
The fomular is: $$area = √(s*(s-a)*(s-b)*(s-c) ) (among which: s=(a+b+c)/2)$$
![ Tim screenshot 20190319145526. PNG] (~ / 658719e7-af42-4e4a-b428-8cd437795f. PNG)
### Input Specification:
Input 3 floating numbers in one line, separate each other by ','.
### Output Specification:
Output the area hold 2 fraction digits
### Sample Input:
```in
4,5,6
```
### Sample Output:
```out
The area is 9.92
```
answer：If there is no answer, please comment