# Program to find sum of harmonic series

Harmonic series is inverse of a arithmetic progression. In general, the terms in a harmonic progression can be denoted as 1/a, 1/(a + d), 1/(a + 2d), 1/(a + 3d) …. 1/(a + nd).
As Nth term of AP is given as ( a + (n – 1)d). Hence, Nth term of harmonic progression is reciprocal of Nth term of AP, which is 1/(a + (n – 1)d), where “a” is the 1st term of AP and “d” is a common difference.

Method #1: Simple approach

## C++

 // C++ program to find sum of harmonic series  #include  using namespace std;     // Function to return sum of harmonic series double sum(int n) {   double i, s = 0.0;   for(i = 1; i <= n; i++)       s = s + 1 / i;            return s; }    // Driver code int main() {     int n = 5;            cout << "Sum is " << sum(n);     return 0; }    // This code is contributed by SHUBHAMSINGH10

## C

 // C program to find sum of harmonic series #include    // Function to return sum of harmonic series double sum(int n) {   double i, s = 0.0;   for (i = 1; i <= n; i++)       s = s + 1/i;   return s; }    int main() {     int n = 5;     printf("Sum is %f", sum(n));     return 0; }

## Java

 // Java Program to find sum of harmonic series import java.io.*;    class GFG {            // Function to return sum of     // harmonic series     static double sum(int n)     {       double i, s = 0.0;       for (i = 1; i <= n; i++)           s = s + 1/i;       return s;     }               // Driven Program     public static void main(String args[])     {         int n = 5;         System.out.printf("Sum is %f", sum(n));             } }

## Python3

 # Python program to find the sum of harmonic series    def sum(n):     i = 1     s = 0.0     for i in range(1, n+1):         s = s + 1/i;     return s;    # Driver Code  n = 5 print("Sum is", round(sum(n), 6))

## C#

 // C# Program to find sum of harmonic series using System;    class GFG {            // Function to return sum of     // harmonic series     static float sum(int n)     {         double i, s = 0.0;                    for (i = 1; i <= n; i++)             s = s + 1/i;                        return (float)s;     }               // Driven Program     public static void Main()     {         int n = 5;                 Console.WriteLine("Sum is "                            + sum(n));             } }

## PHP



Output:

Sum is 2.283333

Method #2: Using recursion

## C++

 // CPP program to find sum of  // harmonic series using recursion  #include using namespace std;    float sum(float n)  {      // Base condition      if (n < 2)          return 1;         else         return 1 / n + (sum(n - 1));  }     // Driven Code  int main()  {     cout << (sum(8)) << endl;      cout << (sum(10)) << endl;      return 0; }     // This code is contributed by // Shashank_Sharma

## Java

 // Java program to find sum of  // harmonic series using recursion  import java.io.*;     class GFG  {     float sum(float n)  {      // Base condition      if (n < 2)          return 1;         else         return 1 / n + (sum(n - 1));  }     // Driven Code  public static void main(String args[])  {    GFG g = new GFG();    System.out.println(g.sum(8));    System.out.print(g.sum(10));  }  }     // This code is contributed by Shivi_Aggarwal

## Python 3

 # Python program to find sum of # harmonic series using recursion    def sum(n):        # Base condition     if n < 2:         return 1        else:         return 1 / n + (sum(n - 1))            print(sum(8)) print(sum(10))

## C#

 //C# program to find sum of  // harmonic series using recursion  using System;    class GFG  {     static float sum(float n)  {      // Base condition      if (n < 2)          return 1;         else         return 1 / n + (sum(n - 1));  }     // Driven Code  public static void Main()  {      Console.WriteLine(sum(8));      Console.WriteLine(sum(10));  }  }     // This code is contributed by shs..

## PHP



Output:

2.7178571428571425
2.9289682539682538

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