diff --git a/ex4.c b/ex4.c
new file mode 100644
index 0000000..fb5b180
--- /dev/null
+++ b/ex4.c
@@ -0,0 +1,85 @@
+#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;
+}