序列2，22，222………

// CPP program to find sum of series

// 2, 22, 222, ..

#include <bits/stdc++.h>

using namespace std;

// function which return the

// the sum of series

float sumOfSeries( int n)

{

return 0.0246 * ( pow (10, n) - 1 - (9 * n));

}

// driver code

int main()

{

int n = 3;

cout << sumOfSeries(n);

return 0;

}

// JAVA Code for Sum of the

// sequence 2, 22, 222,...

import java.util.*;

class GFG {

// function which return the

// the sum of series

static double sumOfSeries( int n)

{

return 0.0246 * (Math.pow( 10 , n)

- 1 - ( 9 * n));

}

/* Driver program */

public static void main(String[] args)

{

int n = 3 ;

System.out.println(sumOfSeries(n));

}

}

// This code is contributed by Arnav Kr. Mandal.

# Python3 code to find

# sum of series

# 2, 22, 222, ..

import math

# function which return

# the sum of series

def sumOfSeries( n ):

return 0.0246 * (math. pow ( 10 , n) - 1 - ( 9 * n))

# driver code

n = 3

print ( sumOfSeries(n))

# This code is contributed by "Sharad_Bhardwaj".

// C# Code for Sum of the

// sequence 2, 22, 222,...

using System;

class GFG {

// Function which return the

// the sum of series

static double sumOfSeries( int n)

{

return 0.0246 * (Math.Pow(10, n)

- 1 - (9 * n));

}

// Driver Code

public static void Main()

{

int n = 3;

Console.Write(sumOfSeries(n));

}

}

// This code is contributed by vt_m.

<?php

// PHP program to find sum

// of series 2, 22, 222, ..

// function which return the

// the sum of series

function sumOfSeries( $n )

{

return 0.0246 * (pow(10, $n ) -

1 - (9 * $n ));

}

// Driver Code

$n = 3;

echo (sumOfSeries( $n ));

// This code is contributed by Ajit.

?>

<script>

// JavaScript program for Sum of the

// sequence 2, 22, 222,...

// function which return the

// the sum of series

function sumOfSeries(n)

{

return 0.0246 * (Math.pow(10, n)

- 1 - (9 * n));

}

// Driver code

let n = 3;

document.write(sumOfSeries(n));

</script>