euler/euler2.cpp at main · puffer3/euler · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
//
// Created by Henry Glover on 8/16/23.
//
//
// fibonacci sequence - add two previous terms
//1,2,3,5,8,13,21,34,55,89
// By considering the terms in the Fibonacci sequence whose values do
// not exceed four million, find the sum of the even-valued terms.
#include <iostream>

// function declaration

void euler2 (int &fibSumEven) ;

int main ()

    {
    int fibSumEven = 0;
    euler2(fibSumEven);
    std::cout << "Sum of Even Fibonacci values below 4 million is : " << fibSumEven << std::endl;
    return 0;

    }

// function definition

void euler2 (int &fibSumEven)

{

    int fibA = 1;
    int fibB = 2;
    int fibC = 0;

    while (fibB < 4000000)

    {
        fibC = fibA + fibB;
        fibA = fibB;
        fibB = fibC;

        if (fibC % 2 == 0)

        {
            fibSumEven += fibC;
            std::cout << "Added to sum even value : "  << fibC << std::endl;
        }
    }

}


/*   this was how I first solved it ::

    for (int i = 0; fibB < 4000000 && fibA < 4000000; ++i) {
        fibC = fibA + fibB;
        fibA = fibB;
        fibB = fibC;
        if (fibC % 2 == 0) {
            fibSumEven = fibSumEven + fibC;
            std::cout << "added to sum even vale : " << fibC << std::endl;
        }
    }

    std::cout << " Sum of Even Fibonachi values below 4 Million is : " << fibSumEven << std::endl;

    }

*/