diff --git a/liste.c b/liste.c
new file mode 100644
index 0000000..6a9f4a4
--- /dev/null
+++ b/liste.c
@@ -0,0 +1,160 @@
+#include <stdio.h>
+#include "Graphique/libgraph.h"
+#include <stdlib.h>
+#include "liste.h"
+#define  TAILLE_X     700
+#define  TAILLE_DESC  40
+#define  LARGEUR_MONS 30
+#define  HAUTEUR_MONS 30
+#define  LARGEUR_VAIS 35
+#define  SPEED        1
+#define  MISS_SPEED   5
+#define  LARGEUR_MISS 5
+#define  HAUTEUR_MISS 10
+
+
+
+
+l_entite* create_l_entite(int x,int y,int speed,int image)
+{ 
+  l_entite* monster_1 =(l_entite*)malloc(sizeof(l_entite));
+  (monster_1->ent).image=image;
+  (monster_1->ent).x    =x;
+  (monster_1->ent).y    =y;
+  (monster_1->ent).speed=speed;
+  monster_1->next       = NULL;
+  return monster_1;
+}
+
+entite create_entite(entite ent,int x,int y, int speed, int image)
+{
+  (ent).image=image;
+  (ent).x    =x;
+  (ent).y    =y;
+  (ent).speed=speed;
+  return ent;
+}
+
+
+  
+void add_entite (l_entite** head,int x,int y,int speed,int image)
+{
+ 
+  l_entite* new_monster = create_l_entite( x, y,speed,image);
+  if (head==NULL)
+     {
+     *head=new_monster;
+    }
+  else
+    {
+     l_entite* current =*head;
+      while (current->next != NULL)
+	{ current=current->next;
+	}
+      current->next=new_monster;
+    }
+}
+
+
+void display_l_entite(l_entite* mons)
+{
+ l_entite* ptr= mons;
+  while(ptr != NULL)
+    {
+      afficherLutin((ptr->ent).image,(ptr->ent).x,(ptr->ent).y);
+      ptr=ptr->next;
+    }
+}
+
+void display_entite(entite ent)
+ {
+    afficherLutin((ent).image,(ent).x,(ent).y);
+ }
+
+
+
+void moveMonster(l_entite* monstre)
+{
+  int max =  TAILLE_X - LARGEUR_MONS;
+  l_entite* currentMonster = monstre;
+  while (currentMonster != NULL)
+    {
+      (currentMonster->ent).x += (currentMonster->ent).speed;
+
+      if ( (currentMonster->ent).x < 0 || (currentMonster->ent).x > max)
+	{
+	  (currentMonster->ent).speed = -(currentMonster->ent).speed;
+	  (currentMonster->ent).y += TAILLE_DESC ;
+	}
+      
+      currentMonster = currentMonster->next;
+    }
+}
+
+
+void addMissile(l_entite** head, entite vaisseau,int image)
+{
+  // int       MI            =chargerLutin("graphique/invader_missile.bmp", COULEUR_NOIR);
+  l_entite* newMissile    = malloc(sizeof(l_entite));
+  (newMissile->ent).x     = vaisseau.x + (LARGEUR_VAIS/2);
+  (newMissile->ent).y     = (vaisseau).y - 5;
+  (newMissile->ent).speed = SPEED;
+  (newMissile->ent).image = image;
+  newMissile->next        = *head;
+  *head                   = newMissile;
+}
+  
+
+
+
+ void moveMissile (l_entite* msl)
+{
+   l_entite* currentMissile = msl;
+  while(currentMissile != NULL)
+    {
+      (currentMissile->ent).y = (currentMissile->ent).y - MISS_SPEED ;
+      currentMissile = currentMissile->next;
+    }
+}
+    
+
+void remove_entite (l_entite** head, l_entite* to_delete)
+{
+     
+      l_entite* courant = *head;
+      while (courant != NULL)
+	{
+	  if ((courant->ent).x == (to_delete->ent).x && (courant->ent).y == (to_delete->ent).y)
+	    {
+	      free(to_delete);
+	    }
+	  courant = courant->next;
+	}
+}
+
+
+void detecterCollisions(l_entite* l_missile, l_entite* l_monstre)
+{
+    l_entite* missile_courant = l_missile;
+    l_entite* monstre_courant = l_monstre;
+
+    while (missile_courant != NULL)
+    {
+        while (monstre_courant != NULL)
+        {
+	  if ( (monstre_courant->ent).x <= (missile_courant->ent).x && (missile_courant->ent).x <= (monstre_courant->ent).x + LARGEUR_MONS &&  (missile_courant->ent).y + HAUTEUR_MISS <= (monstre_courant->ent).y + HAUTEUR_MONS )
+            {
+	       int B=lutinTexte("boom", COULEUR_BLEU);
+	        afficherLutin(B,300,400);
+	      remove_entite(&l_missile,missile_courant);
+	      remove_entite(&l_monstre,monstre_courant);
+	       
+
+	        (missile_courant->ent).image = 0;
+	       (monstre_courant->ent).image = 0;
+            }
+            monstre_courant = monstre_courant->next;
+        }
+        missile_courant = missile_courant->next;
+    }
+}
--
libgit2 0.21.2