diff --git a/srcs/part4.c b/srcs/part4.c
new file mode 100644
index 0000000..a39a07f
--- /dev/null
+++ b/srcs/part4.c
@@ -0,0 +1,61 @@
+#include "../includes/structure.h"
+
+#define MAX_TACHES 100
+
+void calculerDatesDebut()
+{
+	int	file[MAX_TACHES];
+	int	dateActuelle;
+	int	indiceSucc;
+	int	indeTache;
+	int	deb;
+	int	fin;
+	int	i;
+	int	j;
+
+	initialiserFile(file, &deb, &fin);
+
+	for (i = 0; i < nbTaches; i++)
+		if (tableauTaches[i].nbPred == 0)
+			enfiler(file, &fin, i);
+
+	dateActuelle = 0;
+	while (!estVide(deb, fin))
+	{
+		indiceTache = defiler(file, &deb);
+		Tache *t = &tableauTaches[indiceTache];
+
+		t->dateDebut = dateActuelle;
+		t->traite = true;
+		
+		for (j = 0; j < t->nbSucc; j++)
+		{
+			indiceSucc = t->successeurs[j];
+			Tache *succ = &tableauTaches[indiceSucc];
+			if (succ->dateDebut > dateActuelle + t->duree)
+				succ->dateDebut = succ->dateDebut;
+			else
+				succ->dateDebut = dateActuelle + t->duree;
+			succ->nbPred--;
+			
+			if (succ->nbPred == 0)
+				enfiler(file, &fin, indiceSucc);
+		}
+
+		dateActuelle = INT_MAX;
+		for (i = 0; i < nbTaches; i++)
+			if (!tableauTaches[i].traite && tableauTaches[i].dateDebut < dateActuelle)
+				dateActuelle = tableauTaches[i].dateDebut;
+	}
+	
+	for (i = 0; i < nbTaches; i++)
+		if (!tableauTaches[i].traite)
+			printf("Toutes les taches n'ont pas ete executees\n");
+			exit(1);
+}
+
+int	main()
+{
+    return (0);
+}
+