diff --git a/src/movies.ts b/src/movies.ts
index 3dd9e0c..d5d10e6 100644
--- a/src/movies.ts
+++ b/src/movies.ts
@@ -54,8 +54,7 @@ const movies: Movie[] = [
  */
 function hasKey(obj: object, key: string): boolean {
   // write your code here...
-
-  return true; // replace true with what you see is fit
+  return obj.hasOwnProperty(key); // replace true with what you see is fit
 }
 
 /**
@@ -65,6 +64,7 @@ function hasKey(obj: object, key: string): boolean {
  */
 function printMovieTitles(movies: Movie[]): void {
   // write your code here...
+  movies.forEach((movie) => console.log(movie.title));
 }
 
 /**
@@ -80,8 +80,7 @@ function printMovieTitles(movies: Movie[]): void {
  */
 function countMoviesByYear(movies: Movie[], year: number): number {
   // write your code here...
-
-  return -1; // replace -1 with what you see is fit
+  return movies.filter((movie) => movie.year === year).length; // replace -1 with what you see is fit
 }
 
 /**
@@ -109,8 +108,10 @@ function updateMovieGenre(
   newGenre: string
 ): Movie[] {
   // write your code here...
-
-  return []; // replace empty array with what you see is fit
+  movies.forEach((movie) =>
+    movie.title === title ? (movie.genre = newGenre) : movie
+  );
+  return movies; // replace empty array with what you see is fit
 }
 
 export { Movie, hasKey, printMovieTitles, countMoviesByYear, updateMovieGenre };