4 cups cooked macaroni

1 cup sliced celery

1/2 cup sliced scallions

4 tbsp coarsely chopped green pepper

2 tbsp chopped red pepper

4 tbsp pitted, chopped black olives

2 tbsp finely chopped parsley

1 cup mayonnaise

2 tbsp vinegar

1/2 tsp freshly ground black pepper

1 pinch salt to taste