The answer is 12
Ham, swiss, mustard
Ham, swiss, mayonnaise
Ham, provolone, mustard
Ham, provolone, mayonnaise
Turkey, swiss, mustard
Turkey, swiss, mayonnaise
Turkey, provolone, mustard
Turkey, provolone, mayonnaise
Roast beef, swiss, mustard
Roast beef, swiss, mayonnaise
Roast beef, provolone, mustard
Roast beef, provolone, mayonnaise