Cook a Dish

Have you ever cooked something? No? Not a problem! Whenever you try to cook something, you need some ingredients, obviously with some water, oil and heat. May be finally you will manage to cook the dish you wanted. But I am not sure if you will dare to taste it ;) ! Here, you are given some ingredients, you need to tell me how many different recipes are possible from the ingredients? Ingredients will be given as a string S consisting of digits (0-9) where each digit is an ingredient. A recipe is a mixture of some unique ingredients. So, you need to pick up exactly D ingredients from the ingredients in string S to make a recipe. Also, there is a restriction that you can’t use ‘0’ as the first ingredient of a recipe. And keep in mind ‘240’ and ‘420’ are different recipes.

This is a companion discussion topic for the original entry at