Program to find the Perimeter of a Regular Polygon

Given the number of sides 'n' and the length of side 's' of a regular polygon, the task is to find out the Perimeter of this polygon.

Examples: 

Input: n = 7, s = 10
Output: Perimeter : 70
Since the sides are 7,
Hence the given polygon is Heptagon.
Therefore. Perimeter = 7*10 = 70

Input: n = 5, s = 2.5
Output: Perimeter : 12.5
Since the sides are 5,
Hence the given polygon is Pentagon.
Therefore. Perimeter = 5*2.5 = 12.5

Approach: In geometry, a regular polygon is a closed figure with all sides equal. It is a two-dimensional figure. 

Perimeter of a Regular Polygon = Number of sides * Length of each side

Below is the implementation of the above approach: 

// C++ program to find the
// perimeter of a regular polygon

#include <iostream>
using namespace std;

// Function to calculate the perimeter
float Perimeter(float s, int n)
{
    float perimeter = 1;

    // Calculate Perimeter
    perimeter = n * s;

    return perimeter;
}

// driver code
int main()
{

    // Get the number of sides
    int n = 5;

    // Get the length of side
    float s = 2.5, peri;

    // find perimeter
    peri = Perimeter(s, n);

    cout << "Perimeter of Regular Polygon"
         << " with " << n << " sides of length "
         << s << " = " << peri << endl;

    return 0;
}

// C program to find the
// perimeter of a regular polygon

#include <stdio.h>

// Function to calculate the perimeter
float Perimeter(float s, int n)
{
    float perimeter = 1;

    // Calculate Perimeter
    perimeter = n * s;

    return perimeter;
}

// driver code
int main()
{

    // Get the number of sides
    int n = 5;

    // Get the length of side
    float s = 2.5, peri;

    // find perimeter
    peri = Perimeter(s, n);

    printf("Perimeter of Regular Polygon\n"
           " with %d sides of length %f = %f\n",
           n, s, peri);

    return 0;
}

// Java program to find the
// perimeter of a regular polygon

class GFG {

    // Function to calculate the perimeter
    static double Perimeter(double s, int n)
    {
        double perimeter = 1;

        // Calculate Perimeter
        perimeter = n * s;

        return perimeter;
    }

    // Driver method
    public static void main(String[] args)
    {

        // Get the number of sides
        int n = 5;

        // Get the length of side
        double s = 2.5, peri;

        // find perimeter
        peri = Perimeter(s, n);

        System.out.println("Perimeter of Regular Polygon"
                           + " with " + n + " sides of length "
                           + s + " = " + peri);
    }
}

# Python3 program to find the
# perimeter of a regular polygon


# Function to calculate the perimeter
def Perimeter(s, n):
    perimeter = 1
    # Calculate Perimeter
    perimeter = n * s

    return perimeter

# driver code
if __name__== '__main__':
    # Get the number of sides
    n = 5

    #Get the length of side
    s = 2.5
    # find perimeter
    peri = Perimeter(s, n)

    print("Perimeter of Regular Polygon with"
          ,n,"sides of length",s,"=",peri)
    
# This code is contributed by
# SURENDRA_GANGWAR

// C# program to find the 
// perimeter of a regular polygon 
using System;

class GFG
{
// Function to calculate the perimeter 
static double Perimeter(double s, int n) 
{ 
    double perimeter = 1; 

    // Calculate Perimeter 
    perimeter = n * s; 

    return perimeter; 
} 

// Driver Code 
static public void Main ()
{
    // Get the number of sides 
    int n = 5; 

    // Get the length of side 
    double s = 2.5, peri; 

    // find perimeter 
    peri = Perimeter(s, n); 

    Console.WriteLine("Perimeter of Regular Polygon" + 
                      " with " + n + " sides of length " + 
                        s + " = " + peri); 
}
}

// This code is contributed by Sachin

<?php
// PHP program to find the 
// perimeter of a regular polygon

// Function to calculate the perimeter 
function Perimeter($s, $n) 
{ 
    $perimeter = 1; 
  
    // Calculate Perimeter 
    $perimeter = $n * $s; 
  
    return $perimeter; 
} 
  
    // driver code 
    
    // Get the number of sides 
    $n = 5; 
  
    // Get the length of side 
    $s = 2.5; 
  
    // find perimeter 
    $peri = Perimeter($s, $n); 
  
    echo "Perimeter of Regular Polygon"
         ," with ", $n," sides of length "
         ,$s," = ",$peri; 
            
// This code is contributed by ANKITRAI1
?>

<script>

// Javascript program to find the
// perimeter of a regular polygon

// Function to calculate the perimeter
function Perimeter(s, n) 
{
    var perimeter = 1;
    
    // Calculate Perimeter
    perimeter = n * s;
    
    return perimeter;
}

// Driver code

// Get the number of sides
var n = 5;

// Get the length of side
var s = 2.5, peri;

// find perimeter
peri = Perimeter(s, n);

document.write("Perimeter of Regular Polygon<br/>" +
               " with " + n + " sides of length " +
               s.toFixed(6) + " = " + peri.toFixed(6));

// This code is contributed by gauravrajput1

</script>

Perimeter of Regular Polygon 
with 5 sides of length 2.500000 = 12.500000

Time Complexity: O(1), since there is no loop or recursion.
Auxiliary Space: O(1), since no extra space has been taken.