我的代码

Question

我正在尝试解决CS50的贪婪问题，但它无法正确计算。我总是留下0.01而不是0.00的剩余价值。一切都顺利，除了最后的便士。我不知道该怎么做。当您输入更改时，请尝试9.99。没有便士的数字它工作正常。

非常感谢！

int main()
{
    // declaring variables for coins

    float const qtr = 0.25;
    float const dimes = 0.10;
    float const nick = 0.05;
    float const penny = 0.01;

    //declaring variables for coin counters

    int qtr_count = 0;
    int dimes_count = 0;
    int nick_count = 0;
    int penny_count = 0;

    //declaring variables for total debt and rest of debt

    float total;
    float rest;

    //loop for testing is the number entered valid

    do
    {
        printf("Enter the ammount of money he owns:\n");
        scanf("%f", &total);
    }
    while (total < 0.00) ;

    rest = total;

    //Loop for calculating coins

    while (rest >= qtr)
    {
        qtr_count++;
        rest -= 0.25;
    }

    while (rest >= dimes)
    {
        dimes_count++;
        rest -= 0.10;
    }

    while (rest >= nick)
    {
        nick_count++;
        rest -= 0.05;
    }

    while (rest >= penny)
    {
        penny_count++;
        rest -= 0.01;
    }

    printf("You need go give: \n %i quarters, \n %i dimes, \n %i nick, \n %i pennies \n", qtr_count, dimes_count, nick_count, penny_count);

    return 0;

}

Answer 1

问题可能是浮点运算并不总是精确的。我建议你只使用整数。让人输入以美分为单位的金额（或乘以100）。这样你就不会遇到任何浮点运算问题，也会更有效率。