C++ Exercises: Print the area of a polygon

Last update on August 11 2025 12:58:11 (UTC/GMT +8 hours)

Polygon Area Calculation

Write a C++ program to print the area of a polygon.

Visual Presentation:

C++ Exercises: Print the area of a polygon

Sample Solution:

C++ Code :

#include <iostream> // Including input-output stream header file
#include <math.h>   // Including math functions header file

using namespace std; // Using the standard namespace

int main() { // Start of the main function

    float ar, s, n; // Declaration of variables 'ar', 's', and 'n' to store area, side length, and number of sides respectively

    cout << "\n\n Print the area of a polygon:\n"; // Displaying the purpose of the program
	cout << "---------------------------------\n";
	
	cout << " Input the number of sides of the polygon: "; // Prompting user to input the number of sides
	cin >> n; // Taking input from user and storing it in variable 'n'
	
	cout << " Input the length of each side of the polygon: "; // Prompting user to input the side length
	cin >> s; // Taking input from user and storing it in variable 's'
	
	// Calculating the area of the polygon using the formula: n * s^2 / (4 * tan(π / n))
	ar = (n * (s * s)) / (4.0 * tan((M_PI / n))); // M_PI represents the value of π
	
	cout << " The area of the polygon is: " << ar << "\n"; // Displaying the calculated area
	
	return 0; // Returning 0 to indicate successful program execution
}

Sample Output:

Print the area of a polygon:                                          
---------------------------------                                      
 Input the number of sides of the polygon: 7                           
 Input the length of each side of the polygon: 6                       
 The area of the ploygon is: 130.821

Flowchart:

For more Practice: Solve these Related Problems:

Write a C++ program to calculate the area of a regular polygon using the apothem and perimeter, given the number of sides and side length.
Write a C++ program that computes the area of an irregular polygon using the shoelace formula and displays intermediate calculations.
Write a C++ program to calculate the area of a polygon by decomposing it into triangles and summing their areas.
Write a C++ program that takes the number of sides and side lengths of a polygon, then computes and prints its area with error handling for invalid polygons.

Go to:

PREV : Hexagon Area Calculation.
NEXT : Earth Surface Distance.

C++ Code Editor:

Have another way to solve this solution? Contribute your code (and comments) through Disqus.