単方向リスト

main.c

#include <stdio.h>
#include <stdlib.h>

typedef struct Node {
    int data;
    struct Node *next;
} Node;

Node *addNode(Node *list, int data) {
    Node* node = (Node*)malloc(sizeof(Node));
    if (node == NULL) {
        return NULL;
    }
    node->data = data;
    
    if (list == NULL) {
        return node;
    }
    Node *search = list;
    while (search->next != NULL) {
        search = search->next;
    }
    search->next = node;
    return list;
}

Node *searchEnd(Node *list) {
    Node *search = list;
    while (search->next != NULL) {
        search = search->next;
    }
    return search;
}

Node *searchList(Node *list, int data) {
    Node *search = list;
    while (search->next != NULL) {
        if (search->data == data) {
            return search;
        }
        search = search->next;
    }
    return NULL;
}

Node *indexList(Node *list, int index) {
    Node *search = list;
    int counter = 0;
    while (search->next != NULL && counter < index) {
        search = search->next;
        counter += 1;
    }
    return search;
}

void freeList(Node *list) {
    Node *search = list;
    Node *tmp;
    while(search->next != NULL) {
        tmp = search->next;
        free(search);
        search = tmp;
    }
    free(tmp);
}

int main(void) {
    Node *list = NULL;
    
    list = addNode(list, 2);
    list = addNode(list, 5);
    list = addNode(list, 8);
    
    printf("%d\n", indexList(list, 1)->data);
    freeList(list);
    return 0;
}