Sum of numbers from 1 to N which are in Fibonacci Sequence

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Given an integer N, the task is to find the sum of numbers from 1 to N which are in Fibonacci sequence.
First few Fibonacci numbers are 1, 1, 2, 3, 5, 8, 13, 21, 34, ….
Examples:

Input: N = 5
Output: 12
1 + 1 + 2 + 3 + 5 = 12
Input: N = 10
Output: 20
1 + 1 + 2 + 3 + 5 + 8 = 20

Approach:

Loop through all the Fibonacci numbers which are less than N.
Initialize a sum variable with 0.
Keep on adding these Fibonacci numbers to get the required sum.

Below is the implementation of the above approach:

C++

// C++ implementation of the approach 
#include <bits/stdc++.h> 
using namespace std; 
  
// Function to return the 
// required sum 
int fibonacciSum(int N) 
{ 
  
    if (N == 0) 
        return 0; 
  
    // Generate all Fibonacci numbers <= N 
    // and calculate the sum 
    int sum = 0; 
    int a = 1, b = 1, c; 
    sum += a; 
    while (b <= N) { 
  
        sum += b; 
        int c = a + b; 
        a = b; 
        b = c; 
    } 
    return sum; 
} 
  
// Driver code 
int main() 
{ 
    int N = 20; 
    cout << fibonacciSum(N); 
  
    return 0; 
} 

Java

// Java implementation of the approach 
class GFG 
{ 
      
// Function to return the 
// required sum 
static int fibonacciSum(int N) 
{ 
  
    if (N == 0) 
        return 0; 
  
    // Generate all Fibonacci numbers <= N 
    // and calculate the sum 
    int sum = 0; 
    int a = 1, b = 1, c; 
    sum += a; 
    while (b <= N) 
    { 
  
        sum += b; 
        c = a + b; 
        a = b; 
        b = c; 
    } 
    return sum; 
} 
  
// Driver code 
public static void main(String[] args) 
{ 
    int N = 20; 
    System.out.println(fibonacciSum(N)); 
} 
} 
  
// This code is contributed by Code_Mech. 

Python3

# Python3 implementation of  
# the approach  
  
# Function to return the  
# required sum  
def fibonacciSum(N):  
  
    if N == 0: 
        return 0
  
    # Generate all Fibonacci  
    # numbers <= N and calculate 
    # the sum  
    Sum = 0
    a, b = 1, 1
    Sum += a  
    while b <= N:  
  
        Sum += b  
        a, b = b, a + b  
      
    return Sum
  
# Driver code  
if __name__ == "__main__":  
  
    N = 20
    print(fibonacciSum(N))  
  
# This code is contributed  
# by Rituraj Jain 

C#

// C# implementation of the approach 
using System; 
  
class GFG 
{ 
      
// Function to return the 
// required sum 
static int fibonacciSum(int N) 
{ 
  
    if (N == 0) 
        return 0; 
  
    // Generate all Fibonacci numbers <= N 
    // and calculate the sum 
    int sum = 0; 
    int a = 1, b = 1, c; 
    sum += a; 
    while (b <= N) 
    { 
  
        sum += b; 
        c = a + b; 
        a = b; 
        b = c; 
    } 
    return sum; 
} 
  
// Driver code 
public static void Main() 
{ 
    int N = 20; 
    Console.WriteLine(fibonacciSum(N)); 
} 
} 
  
// This code is contributed by Code_Mech. 

PHP

<?php 
// PHP implementation of the approach 
  
// Function to return the 
// required sum 
function fibonacciSum($N) 
{ 
    if ($N == 0) 
        return 0; 
  
    // Generate all Fibonacci numbers <= N 
    // and calculate the sum 
    $sum = 0; 
    $a = 1; $b = 1; $c; 
    $sum += $a; 
    while ($b <= $N) 
    { 
        $sum += $b; 
        $c = $a + $b; 
        $a = $b; 
        $b = $c; 
    } 
    return $sum; 
} 
  
// Driver code 
$N = 20; 
  
echo(fibonacciSum($N)); 
  
// This code is contributed  
// by Code_Mech. 
?> 

Javascript

<script> 
  
// Javascript implementation of the approach 
  
// Function to return the 
// required sum 
function fibonacciSum(N) 
{ 
  
    if (N == 0) 
        return 0; 
  
    // Generate all Fibonacci numbers <= N 
    // and calculate the sum 
    var sum = 0; 
    var a = 1, b = 1, c; 
    sum += a; 
    while (b <= N) { 
  
        sum += b; 
        var c = a + b; 
        a = b; 
        b = c; 
    } 
    return sum; 
} 
  
// Driver code 
var N = 20; 
document.write( fibonacciSum(N)); 
  
</script>

Output:

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