Problem #18
Solution Source Code
Code Overview
1. Header Files and Namespace:
<iostream>is included for input and output operations.<string>is included for potential future use (not used in this program).<cmath>is included to usepow()for exponentiation (R²).using namespace std;allows the use of standard functions without prefixing them withstd::.
2. User Input Function (ReadRadius)
- Prompts the user to enter the radius (R) of a circle.
- Reads and returns the radius.
3. Area Calculation Function (CircleArea)
- Takes the radius (R) as input.
- Uses the standard formula for the area of a circle:
float Area = pow(R, 2) * PI;
pow(R, 2)calculatesR².PIis defined as3.141592653589793238for precise calculations.
- Returns the computed area.
4. Output Function (PrintResult)
- Receives the computed area as a parameter.
- Prints
"Circle Area = [Area]".
5. Program Execution (main())
- Calls
ReadRadius()to get user input. - Calls
CircleArea()to compute the area. - Calls
PrintResult()to display the result. - Returns
0to indicate successful execution.
This structured explanation ensures clarity and ease of understanding.

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