diff --git a/technical-fundamentals/coding/__tests__/connect4.test.mjs b/technical-fundamentals/coding/__tests__/connect4.test.mjs
index 21e1f125..64cd5898 100644
--- a/technical-fundamentals/coding/__tests__/connect4.test.mjs
+++ b/technical-fundamentals/coding/__tests__/connect4.test.mjs
@@ -17,7 +17,7 @@ describe("Connect4", () => {
 
   it("it should detect horizontal winning", () => {
     const c4 = new Connect4({ width: 10, height: 10 });
-    for (let i = 0; i < 4; i++) {
+    for (let i = 1; i <= 4; i++) {
       c4.play(i);
       c4.play(i);
     }