Write a program in C that prints the first 50 Fibonacci numbers, starting with 1 and 2

To be able to answer this question, you need to understand what a fibonacci number is and how to derive a fibonacci sequence.

A fibnonacci number is any number in a sequence which happens to be the sum of the two preceeding numbers.

This means that the number n in a sequence will be expressed as:

n = (n-1) + (n-2)

For instance, this question states the numbers (1, 2) we should use to start our fibonacci sequence. This means that our sequence will be something like

This means that if we assign our first two numbers to variables first and second and declare another variable called next, we can go ahead to represent them as.

int first = 1;
int second = 2;
int next = first + second;

In the above case, the next variable becomes 3. As soon as we get that one, we need to find what the next one after 3 will be.

Since we are interested in what is after 3, we will need to reset our first and second variables. You will realize that to get the number after 3, our first variable now becomes 2 and the second variable becomes 3. This gives us:

first = 2;
second = 3;
next = first + second;
=> next = 2 + 3; 
=> next = 5;

The process will then repeated for the variable first to become 3 and second become 5. The next variable becomes 8 which is 3 + 5.

I bet you now know how this works. If you don't, kindly go over it again to understand the steps. We can then go ahead and implement this concept as a C program.

Coding a C program that prints the first 50 numbers

Below is the code in C program that does exactly what we have discussed about.

#include <stdio.h>

/**
 * main - main block
 * Description: Print the first 50 fibonacci numbers, starting with 1 and 2.
 * Numbers must be coma and space separated.
 * Return: 0
 */

int main(void)
{
    int count = 3; /* this is so because the first 2 members have been given already. My loop will therefore begin from the 3rd one */

    long int first = 1, second = 2;
    long int next = first + second;

    printf("%lu, ", first);
    printf("%lu, ", second);

    while (count <= 50)
    {
        /* Let's check if we are at the end of the list, if we are close with a new line */
        if (count == 50)
        {
            printf("%lu \n", next);
         }
         else  /* if we are not at the end of the list, add a comma after the number */
         { 
           printf("%lu, ", next); 
         }

        /* Reset the variables to get the next number */
        first = second;
        second = next;

        /* after resetting the variables, you need to find the next number */
        next = first + second; 
        count++;
    }

    return (0);
}

The output of the above code is:

1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765, 10946, 17711, 28657, 46368, 75025, 121393, 196418, 317811, 514229, 832040, 1346269, 2178309, 3524578, 5702887, 9227465, 14930352, 24157817, 39088169, 63245986, 102334155, 165580141, 267914296, 433494437, 701408733, 1134903170, 1836311903, 2971215073, 4807526976, 7778742049, 12586269025, 20365011074

Conclusion

I hope you enjoyed reading this and it made you understand how to solve a problem like this. I would like to hear back from you. Is there anything I missed, or explained wrongly, or something you want me to elaborate more on?

Share with me what you also think. Mind you, I am also learning and your feedback will be valuable to me.

Thanks for reading and I would love to connect personally with you. If you are on Twitter, then you can send me a DM and let's have a good chat.

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Dr. Ehoneah Obed

Heya! One thing I love doing is helping people and I believe one of the key ways I do this is through sharing of my knowledge and personal experiences. I have therefore decided to use this platform to share my knowledge and experience to people who may decide to take the path that I have taken. So, the question is, what is this path? I am professionally trained as a pharmacist but I have been an ardent lover and user of various technologies. During my practice at a tertiary hospital in the Northern Region of Ghana, I discovered a number of pertinent health problems and how technology can be used to solve those problems. In my quest for finding ways to solve some of these health problems with technology, I discovered the field of digital health and how that is transforming the way healthcare is being delivered. I am so much interested in the field and look forward to building a career in digital health and hopefully starting a company (startup) in that field. To make this career transition, I have to pursue further education and I have come across several paths that can lead to that career goal of mine. I have therefore decided to explore almost all the options that I have. For further studies, some of the courses which I came across that can help me achieve that career goal include a masters program or PHD in any of the following: Digital Health, Health technology, Health Informatics, Information Technology, Computer Science and Computational Science. I have therefore started applying to various schools offering any of the programs above. In the time being, I decided to start learning more about emerging technologies and that led me to take a three months course in Amazon Web Services (AWS). I am currently an AWS Certified Cloud Practitioner. During the 3 months training that I undertook at Ghana Tech Lab, Accra, I was introduced to a lot of things which excited me the more. I came to realize the potential of things I could do if I had the right knowledge especially in software development. Prior to this time, I had taught myself a number programming languages, libraries and frameworks for web development. I could consider myself as a fullstack developer with knowledge in HTML, CSS, Javascript, PHP, MySQL, WordPress, React, Laravel, and Codeigniter. However, I practiced less and didn't feel confident enough about my knowledge. I just knew I needed more. More learning, more practice, more projects and more connections with people in the industry. I started taking the Odin project to become a better web developer and a few days into it, I came across the ALX Software Engineering programme for Africans. Once I realized it was free to join, I was going to do everything in my capacity to qualify for it. I discovered the programme about 3 days to the deadline for the May 2022 Cohort. I therefore, sat through that night to finish my application to ALX. Fortunately for me, I got accepted into the program and a new phase of my life has started. I am now a Software Engineering Student looking forward to building a career in digital health. I know that this is just the beginning. As part of this programme, we spend about 70 hours a week learning, practicing, completing projects and building new relationships with our peers. As part of this journey, I am going to use this platform to document what I learn and share my journey to becoming a Software Engineer with you. Therefore, anyone at all looking to transition from their current career to software engineering will find what I post here relevant. Also, if you are a self-taught developer or you are thinking of teaching yourself software development, then you will also enjoy the content I publish here. Throughout my short journey of life, I have realized that we tend to give up on things easily when there is no form of accountability. I am therefore by this platform signing a deal to become accountable to you through sharing with you whatever I learn. Do share your thoughts and comments with me whenever you come across any of my post so I can truly remain accountable to you and never give up on this new found dream of mine.