Commit 2f112076 authored by Chris's avatar Chris
Browse files

created cache of fibonacci numbers

parent b8d08aa6

fibonacci_ops.c

+38 −2
Original line number Diff line number Diff line
@@ -2,8 +2,44 @@ 
// Created by Chris on 9/12/25.

//



#include <stdio.h>



#include "fibonacci_ops.h"

#include "linked_list.h"



// linked list to cache the fibonacci numbers



// create a linked list to cache the fibonacci numbers

linked_list_item *fibonacci_first_element = NULL;

linked_list_item **fibonacci_head = &fibonacci_first_element;



// create the ability to calculate next value on demand based on the current linked list



unsigned int get_fibonacci_value_at(unsigned int index) {

    fibonacci_head = &fibonacci_first_element;



    unsigned int current_i = 0;

    unsigned int current_value = 0;



    unsigned int a = 1;

    unsigned int b = 0;

    for (current_i = 0; current_i < index; current_i++) {

        if (*fibonacci_head == NULL) {

            push(fibonacci_head, next_fibonacci_number(a, b));

        }



        current_value = (*fibonacci_head)->value;

        if (current_i % 2 == 0) {

            a = (*fibonacci_head)->value;

        } else {

            b = (*fibonacci_head)->value;

        }

        // iterate to next element

        fibonacci_head = &(*fibonacci_head)->next;

    }



    return current_value;

}



unsigned int next_fibonacci_number(const unsigned int a, const unsigned int b) {

    return a + b;

}

fibonacci_ops.h

+3 −0
Original line number Diff line number Diff line 
#pragma once

//

// Created by Chris on 9/12/25.

//
@@ -5,4 +6,6 @@ 
#ifndef FIBONACCI_STEP_SEARCH_FIBONACCI_OPS_H

#define FIBONACCI_STEP_SEARCH_FIBONACCI_OPS_H



unsigned int get_fibonacci_value_at(unsigned int index);

unsigned int next_fibonacci_number(unsigned int a, unsigned int b);

#endif //FIBONACCI_STEP_SEARCH_FIBONACCI_OPS_H
 
 No newline at end of file

linked_list.c

+3 −3
Original line number Diff line number Diff line
@@ -4,7 +4,7 @@ 
// Created by Chris on 9/12/25.

//



linked_list_item *create_node(unsigned int value) {

linked_list_item *create_node(const unsigned int value) {

    linked_list_item *node = malloc(sizeof(*node));

    if (node == NULL) {

        return NULL;
@@ -14,7 +14,7 @@ linked_list_item *create_node(unsigned int value) { 
    return node;

}



int push(linked_list_item **head, unsigned int value) {

int push(linked_list_item **head, const unsigned int value) {

    linked_list_item *new_node = create_node(value);

    if (new_node == NULL) {

        return -1;

linked_list.h

+3 −1
Original line number Diff line number Diff line 
#pragma once

//

// Created by Chris on 9/12/25.

//
@@ -10,10 +11,11 @@ typedef struct linked_list_item linked_list_item; 
struct linked_list_item {

    unsigned int value;

    linked_list_item *next;

    // linked_list_item *prev;

    linked_list_item *prev;

};



int push(linked_list_item **head, unsigned int value);

void delete_linked_list(linked_list_item **head);

// unsigned int get_at(linked_list_item **head, unsigned int index);



#endif //FIBONACCI_STEP_SEARCH_LINKED_LIST_H
 
 No newline at end of file

main.c

+30 −24
Original line number Diff line number Diff line 


#include <stdio.h>

#include <stdlib.h>



#include "fibonacci_ops.h"

#include "linked_list.h"



int main(void) {

    linked_list_item *first_element = NULL;

    linked_list_item **head = &first_element;



    push(head, 2);

    push(head, 3);

    push(head, 1);



    head = &first_element;



    while ((*head) != NULL) {

        printf("value is %d\n", (*head)->value);

        head = &(*head)->next;

    // -> here's a linked list test

    // linked_list_item *first_element = NULL;

    // linked_list_item **head = &first_element;

    //

    // push(head, 2);

    // push(head, 3);

    // push(head, 1);

    //

    // head = &first_element;

    //

    // while ((*head) != NULL) {

    //     printf("value is %d\n", (*head)->value);

    //     head = &(*head)->next;

    // }

    //

    // head = &first_element;

    // delete_linked_list(head);

    //

    // // sanity check: this should print nothing

    // head = &first_element;

    // while ((*head) != NULL) {

    //     printf("value is %d\n", (*head)->value);

    //     head = &(*head)->next;

    // }



    // -> here's a fibonacci number test

    for (unsigned int i = 0; i < 10; i++) {

        printf("fibonacci number: %d \n", get_fibonacci_value_at(i));

    }



    head = &first_element;

    delete_linked_list(head);



    // sanity check: this should print nothing

    head = &first_element;

    while ((*head) != NULL) {

        printf("value is %d\n", (*head)->value);

        head = &(*head)->next;

    }





    return 0;

}