diff --git a/TD4 Debug/Exercice.ts b/TD4 Debug/Exercice.ts
index d578ca383271425f5fc21361d97930eb15115fba..65dcecaccc6f66fbf7a67ea92fa05b0b900e9de8 100644
--- a/TD4 Debug/Exercice.ts	
+++ b/TD4 Debug/Exercice.ts	
@@ -109,5 +109,18 @@ deb7Opti(-5,3)
 deb7Opti(5,-3)
 
 function deb7Opti(x : number , y : number): number { 
-    return x * y ;
-}
\ No newline at end of file
+    return x * y ; // plus efficace 
+}
+
+// Exercice 8 
+
+let n=5 ; 
+console.log(deb8(n)); //  la fonction calcule 5! = 120
+function deb8(n : number ):number {
+    if (n=== 0){
+        return  1 ;
+    }
+    let valeur = n * deb8(n-1);
+    return valeur ; 
+}
+