Following package directions, cook macaroni in a large kettle of boiling salted water until tender. Drain, rinse with cold water; drain again. Turn into a large bowl. Combine artichokes and their liquid, mushrooms, tomatoes and olives. Add mixture to cooked macaroni and toss gently. Cover and refrigerate for at least 4 hours, or until next day. Before serving, season with salt and pepper to taste. Makes 4 to 6 servings.