C/Visual C - algoritmo de RADIX CON pilass un favor

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

typedef struct Node {

    int data;

    struct Node* next;

} Node;

void append(Node** head_ref, int new_data) {

    Node* new_node = (Node*)malloc(sizeof(Node));

    Node* last = *head_ref;

    new_node->data = new_data;

    new_node->next = NULL;

    if (*head_ref == NULL) {

        *head_ref = new_node;

        return;

    }

    while (last->next != NULL) {

        last = last->next;

    }

    last->next = new_node;

}

void printList(Node* node) {

    while (node != NULL) {

        printf("%d -> ", node->data);

        node = node->next;

    }

    printf("NULL\n");

}

int getMax(Node* head) {

    int max = head->data;

    while (head != NULL) {

        if (head->data > max) {

            max = head->data;

        }

        head = head->next;

    }

    return max;

}

void countingSort(Node** head_ref, int exp) {

    Node* output = NULL; // Lista de salida

    int count[10] = {0};

    Node* current = *head_ref;

    // Contar ocurrencias

    while (current != NULL) {

        count[(current->data / exp) % 10]++;

        current = current->next;

    }

    // Cambiar count para que contenga la posición real de este dígito en output

    for(int i = 1; i < 10; i++) {

        count += count[i - 1];

    }

    // Construir la lista de salida

    current = *head_ref;

    while (current != NULL) {

        int index = (current->data / exp) % 10;

        append(&output, current->data);

        count[index]--;

        current = current->next;

    }

    // Copiar la lista de salida a head_ref

    *head_ref = output;

}

void radixSort(Node** head_ref) {

    int max = getMax(*head_ref);

    for (int exp = 1; max / exp > 0; exp *= 10) {

        countingSort(head_ref, exp);

        printf("Lista después de ordenar por el dígito en la posición %d: ", exp);

        printList(*head_ref);

    }

}

int main() {

    Node* head = NULL;

    append(&head, 170);

    append(&head, 45);

    append(&head, 75);

    append(&head, 90);

    append(&head, 802);

    append(&head, 24);

    append(&head, 2);

    append(&head, 66);

    printf("Lista original: ");

    printList(head);

    radixSort(&head);

    printf("Lista ordenada: ");

    printList(head);

    return 0;

}