C#: Calculate the harmonic series and their sum

Last update on August 21 2025 12:54:11 (UTC/GMT +8 hours)

Write a program in C# Sharp to display the n terms of harmonic series and their sum. The series is :
1 + 1/2 + 1/3 + 1/4 + 1/5 ... 1/n terms

Visual Presentation:

C# Sharp Exercises: Calculate the harmonic series and their sum

Sample Solution:

C# Sharp Code:

using System;  // Importing necessary namespace

public class Exercise19  // Declaration of the Exercise19 class
{  
    public static void Main()  // Main method, entry point of the program
    {
        int i, n;       // Declaration of variables of type integer
        double s = 0.0; // Declaration of a variable of type double, initialized to 0.0

        Console.Write("\n\n");  // Displaying new lines
        Console.Write("Calculate the harmonic series and their sum:\n");  // Displaying the purpose of the program
        Console.Write("----------------------------------------------");  // Displaying a separator
        Console.Write("\n\n");

        Console.Write("Input the number of terms : ");  // Prompting the user to input the number of terms
        n = Convert.ToInt32(Console.ReadLine());    // Reading the number of terms entered by the user

        Console.Write("\n\n");

        // Loop to display and calculate the sum of the harmonic series
        for (i = 1; i <= n; i++)
        {
            Console.Write("1/{0} + ", i);  // Displaying the term of the harmonic series
            s += 1 / (float)i;  // Calculating and adding the current term to the sum
        }

        Console.Write("\nSum of Series upto {0} terms : {1} \n", n, s);  // Displaying the sum of the series
    } 
}

Sample Output:

                                                                                                                                                               
Calculate the harmonic series and their sum:                                                                                                                   
----------------------------------------------                    
Input the number of terms : 6                                                                                                         
1/1 + 1/2 + 1/3 + 1/4 + 1/5 + 1/6 +                                                                                                         
Sum of Series upto 6 terms : 2.45

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