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


typedef struct Point {
    float x, y;
} Point;


typedef struct Node {
    Point point;
    struct Node *next;
} Node;


Node* createNode(float x, float y) {
    Node* newNode = (Node*)malloc(sizeof(Node));
    if (newNode == NULL) {
        printf("Erreur d'allocation mémoire\n");
        exit(1);
    }
    newNode->point.x = x;
    newNode->point.y = y;
    newNode->next = NULL;
    return newNode;
}


void printList(Node* head) {
    Node* current = head;
    while (current != NULL) {
        printf("(%.2f, %.2f) -> ", current->point.x, current->point.y);
        current = current->next;
    }
    printf("NULL\n");
}


void removeNegativePoints(Node** headRef) {
    Node* current = *headRef;
    Node* prev = NULL;

    while (current != NULL) {
        if (current->point.x < 0 && current->point.y < 0) {
            Node* temp = current;
            if (prev == NULL) {
                *headRef = current->next; 
            } else {
                prev->next = current->next; 
            }
            current = current->next;
            free(temp);
        } else {
            prev = current;
            current = current->next;
        }
    }
}


int main() {
    
    Node* head = createNode(1.0, 2.0);
    head->next = createNode(-1.0, -3.0);
    head->next->next = createNode(4.0, -2.0);
    head->next->next->next = createNode(-2.0, -2.0);
    head->next->next->next->next = createNode(5.0, 6.0);

    printf("Liste avant la suppression des points négatifs :\n");
    printList(head);

    removeNegativePoints(&head);

    printf("Liste après la suppression des points négatifs :\n");
    printList(head);

   
    while (head != NULL) {
        Node* temp = head;
        head = head->next;
        free(temp);
    }

    return 0;
}