PROGRAMMING:Input radius (greater than 0), calculate circle area math library
This topic requires the input radius (greater than 0), using the PI constant in math library to calculate the circle area.
Note: if the data of the input radius does not meet the conditions, repeat the input until the conditions are met before entering the subsequent calculation.
###Input format:
Enter a number.
###Output format:
The area of a circle with radius result1 is result2
Among them:
Result1 is the radius
Result2 is the area of the circle, the output width is 10, and 5 decimal places are reserved
###Input example:
Here is a set of inputs. For example:
```in
five
```
###Output example:
The corresponding output is given here. For example:
```out
The area of a circle with radius 5 is 78.53982
```
answer：If there is no answer, please comment
Note: if the data of the input radius does not meet the conditions, repeat the input until the conditions are met before entering the subsequent calculation.
###Input format:
Enter a number.
###Output format:
The area of a circle with radius result1 is result2
Among them:
Result1 is the radius
Result2 is the area of the circle, the output width is 10, and 5 decimal places are reserved
###Input example:
Here is a set of inputs. For example:
```in
five
```
###Output example:
The corresponding output is given here. For example:
```out
The area of a circle with radius 5 is 78.53982
```
answer：If there is no answer, please comment