package Main;

import java.util.ArrayList;
import java.util.List;

public class Main {
    List<Ingredients> ingredients = new ArrayList<>();
    
    public enum Ingredients { 
        SUGAR(0.25), // these are the problem
        MILK(1.25), // this
        CREAM(1.75); // and this one
        
        private final float cost;

        Ingredients(int cost) {
            this.cost = cost;
        }

        public float getCost() {
            return cost;
        }
    }

    public enum Sizes {
        SMALL(5),
        MEDIUM(10),
        LARGE(15);
        
        private final int cost;

        Sizes(int cost) {
            this.cost = cost;
        }

        public int getCost() {
            return cost;
        }
    }

    public static float calculateCost(Sizes size, List<Ingredients> ingredients) {
        int totalCost = size.getCost();
        for (Ingredients ingredient : ingredients) {
            totalCost += ingredient.getCost();
        }
        return totalCost;
    }

    public static void main(String[] args) {
        List<Ingredients> ingredients = new ArrayList<>();
        ingredients.add(Ingredients.MILK);
        ingredients.add(Ingredients.SUGAR);
        System.out.println("Cost of a small size coffee with milk and suger: " + calculateCost(Sizes.SMALL, ingredients));
    }

i was expecting a float with the number

6.5

this was the output

Exception in thread "main" java.lang.NullPointerException: Cannot invoke "Main.Main$Ingredients.getCost()" because "ingredient" is null
    at Java/Main.Main.calculateCost(Main.java:44)
    at Java/Main.Main.main(Main.java:53)

it says that this is a problem

totalCost += ingredient.getCost();

but is was not a problem earlier until i made the enum ingredients a float

i am fairly new to coding in java so i don’t really know much about enums so i might learn more about them later