diff --git a/qualdev/debog/exo3.ts b/qualdev/debog/exo3.ts
new file mode 100644
index 0000000000000000000000000000000000000000..42ad14e4697e0fad21ae1fd0309f1c22f92d0f1a
--- /dev/null
+++ b/qualdev/debog/exo3.ts
@@ -0,0 +1,11 @@
+function deb2(x: number, y: number): void {
+    const tmp = y;
+    y = x;
+    x = tmp;
+    console.log(x, y);
+}
+
+let x = 10;
+let y = 20;
+deb2(x, y);
+console.log(x,y);
\ No newline at end of file