Apply Discount Every n Orders

class Cashier {
    private int n;
    private double discount;
    Map<Integer, Integer> map;
    private int count;
    public Cashier(int n, int discount, int[] products, int[] prices) {
        this.n = n;
        this.discount = discount;
        map = new HashMap();
        for (int i = 0; i < products.length; i++)
            map.put(products[i], prices[i]);
        count = 0;
    }
    
    public double getBill(int[] product, int[] amount) {
        count++;
        double sum = 0;
        for(int i = 0; i<product.length; i++){
            sum += map.get(product[i]) * amount[i];
        }
        
        if(count!=n){
            return sum;
        }
        count=0;
        return sum - ((discount * sum)/100);
    }
}

/**
 * Your Cashier object will be instantiated and called as such:
 * Cashier obj = new Cashier(n, discount, products, prices);
 * double param_1 = obj.getBill(product,amount);
 */