我缺少什么？ 我尝试了很多方法来解决这个问题。

运送包裹的费用为 75 美分的固定费用加上每磅 25 美分。
1. 声明一个名为 CENTS_PER_POUND 的常量并使用 25 进行初始化。
2. 从用户输入中获取运输重量，并将重量存储到shipWeightPounds 中。
3. 使用 FLAT_FEE_CENTS 和 CENTS_PER_POUND 常量，将shipCostCents 指定为运输称重shipWeightPounds 的包裹的成本。

我尝试过的：

import java.util.Scanner;

public class ShippingCalculator {
   public static void main(String[] args) {
      Scanner scnr = new Scanner(System.in);
      int shipWeightPounds;
      int shipCostCents = 0;
      final int FLAT_FEE_CENTS = 75;
      final double CENTS_PER_POUND = 25;
      
      shipWeightPounds = scnr.nextDouble();
      shipCostCents = FLAT_FEE_CENTS + (CENTS_PER_POUND * shipWeightPounds);

      System.out.println("Weight(lb): " + shipWeightPounds);
      System.out.println("Flat fee(cents): " + FLAT_FEE_CENTS);
      System.out.println("Cents per pound: " + CENTS_PER_POUND);
      System.out.println("Shipping cost(cents): " + shipCostCents);
   }
}