使用整数代替十进制

我在做作业时遇到了麻烦。这似乎是不可能的。问题是这样的……

"将来，你可能会使用其他没有像decimal这样支持精确货币计算类型的编程语言。在这些语言中，应该使用整数执行此类计算。修改应用程序，使其仅使用整数来计算复利。将所有货币金额视为便士的整数。然后分别使用除法和余数运算将结果分解为美元和美分两个部分。在显示结果时，在美元和美分部分之间插入句号。"

当我遵循指示并使用整数时，我甚至在除法之前就得到了这些溢出错误。有人知道怎么做吗?这是需要修改的原始代码…

        decimal amount; //amount on deposit at end of each year
        decimal principal = 1000; //initial amount before interest
        double rate = 0.05; //interest rate
        //display headers
        Console.WriteLine("Year{0,20}", "Amount on deposit");
        //calculate amount on deposit for each of ten years
        for (int year = 1; year <= 10; year++)
        {
            //calculate new amount for specified year
            amount = principal *
                ((decimal)Math.Pow(1.0 + rate, year));
            //display the year and the amount
            Console.WriteLine("{0,4}{1,20:C}", year, amount);
        }

这是我到目前为止的代码…

        long amount; //amount on deposit at end of each year
        long principal = 100000; //initial amount before interest
        long rate = 5; //interest rate
        long number = 100;
        //display headers
        Console.WriteLine("Year{0,20}", "Amount on deposit");
        //calculate amount on deposit for each of ten years
        for (int year = 1; year <= 10; year++)
        {
            //calculate new amount for specified year
            amount = principal *
                ((long)Math.Pow(100 + rate, year));
            amount /= number;
            number *= 10;
            //display the year and the amount
            Console.WriteLine("{0,4}{1,20}", year, amount);

它得到一些正确的数字，但由于某种原因，它开始吐出负数。

int amount;
//...some code...
//let's pretend we have an amount of 100.97
amount = (int)(100.97 * 100); // amount = 10097

amount = principal *
    ((long)Math.Pow(100 + rate, year));

double dRate = (double)(100 + rate);
double dYear = (double)year;
double dPow = Math.Pow(dRate, dYear);
amount = principal * (long)dPow;