Find the average of first N natural numbers
Write a program to find the Average of first N natural number.
Examples:
Input : 10
Output : 5.5
1+2+3+4+5+6+7+8+9+10 = 5.5
Input : 7
Output : 4.0
1+2+3+4+5+6+7 = 4
Prerequisite : Sum of first n natural numbers.
As discussed in previous post, sum of n natural number n(n+1)/2, we find the Average of n natural number so divide by n is n(n+1)/2*n = (n+1)/2. Here 1 if first term and n is last term.
// CPP Program to find the Average of first
// n natural numbers
#include <bits/stdc++.h>
using namespace std;
// Return the average of first n natural numbers
float avgOfFirstN(int n)
{
return (float)(1 + n)/2;
}
// Driven Program
int main()
{
int n = 20;
cout << avgOfFirstN(n) << endl;
return 0;
}
// Java Program to find the Average of first
// n natural numbers
import java.io.*;
class GFG {
// Return the average of first n
// natural numbers
static float avgOfFirstN(int n)
{
return (float)(1 + n) / 2;
}
// Driven Program
public static void main(String args[])
{
int n = 20;
System.out.println(avgOfFirstN(n));
}
}
/*This code is contributed by Nikita tiwari.*/
// C#Program to find the Average of first
// n natural numbers
using System;
class GFG {
// Return the average of first n
// natural numbers
static float avgOfFirstN(int n)
{
return (float)(1 + n) / 2;
}
// Driven Program
public static void Main()
{
int n = 20;
Console.WriteLine(avgOfFirstN(n));
}
}
/*This code is contributed by vt_m.*/
<script>
// javascript Program to find the Average of first
// n natural numbers
// Return the average of first n natural numbers
function avgOfFirstN( n)
{
return (1 + n)/2;
}
// Driven Program
let n = 20;
document.write(avgOfFirstN(n));
// This code is contributed by todaysgaurav
</script>
<?php
// PHP Program to find
// the Average of first
// n natural numbers
// Return the average
// of first n natural
// numbers
function avgOfFirstN($n)
{
return (float)(1 + $n) / 2;
}
// Driver Code
$n = 20;
echo(avgOfFirstN($n));
// This code is contributed by Ajit.
?>
# Python 3 Program to find the Average
# of first n natural numbers
# Return the average of first n
# natural numbers
def avgOfFirstN(n) :
return (float)(1 + n) / 2;
# Driven Program
n = 20
print(avgOfFirstN(n))
# This code is contributed by Nikita Tiwari.
Output:
10.5
Time Complexity: O(1)
Auxiliary Space: O(1)