Question

#include <stdio.h>              /*printf and scanf option*/
#include <math.h>

void change(double coin_change, int *quarters, int *dimes, int *nickels, int *pennies);          /*function protype*/

int main(void)
{
    int fifties = 0, twenties = 0, tens = 0, fives = 0, dollars = 0, quarters = 0, dimes = 0, nickels = 0, pennies = 0;
    double amt_paid = 0, amt_due = 0, amt_change = 0, coin_change = 0;          /*declared avriables*/

    printf("Enter the amount paid> ");                  /*Prompt user to enter amount paid*/
    scanf("%lf", &amt_paid);

    printf("Enter the amount due> ");                   /*Prompt user to enter amount due*/
    scanf("%lf", &amt_due);

    amt_change = amt_paid - amt_due;                    /*Formula for amount of change to be given*/
    dollars = (amt_change);

    coin_change = (int)((amt_change - (amt_change)) * 100 + 0.5);
    coin_change = coin_change * 100;
    printf("\n%f\n", coin_change);

    change(coin_change, &quarters, &dimes, &nickels, &pennies);

    printf("Change is fifties: %d$, twenties: %d$, tens: %d$, fives: %d$, dollars: %d$, quarters: %d, dimes: %d, nickels: %d,\
           pennies: %d", fifties, twenties, tens, fives, dollars, quarters, dimes, nickels, pennies);  
    return(0);
}

void change(double coin_change, int *quarters, int *dimes, int *nickels, int *pennies)
{
    int q = 1, d = 1, n = 1, p = 1;
    do {
        if(coin_change >= 25){
            *quarters = *quarters + q;
            coin_change = coin_change - 25;
        }
        else if (coin_change >= 10) {
            *dimes = *dimes + d;
            coin_change = coin_change - 10;
        }
        else if (coin_change  >=  5) {
            *nickels = *nickels + n;
            coin_change = coin_change - 5;
        }
        else if (coin_change >= 1) {
            *pennies = *pennies + p;
            coin_change = coin_change - 1;
        }
    } while (coin_change >= 1);
}

对不起，我第一次不太清楚。我需要的是创建基本上是收银机程序。当给出应付金额，以及从用户支付的金额时，我应该收到输出，告诉我多少50美元的钞票，20s，10s，5s，1s，quarter，dimes，nickels和pennies我应该收到更改。由于我是编程新手，所以您看到的代码就是我所知的最佳代码。我确实需要改进甚至完全改变它。我真正想做的是找出我的错误并修复它们。我希望尽快完成这些代码。我觉得我很亲密，但只是错过了它。也许我错了，但这就是我要来找你们的。

Answer 1

有几件事：

您有许多未使用的变量：fifties，twenties，tens，fives，dollars等。
这里的行：

coin_change = (int)((amt_change - (amt_change)) * 100 + 0.5);
coin_change = coin_change * 100;

错了。它们应该替换为以下内容：

coin_change = (100 * amt_change)。
您是否听说过+= / -=运营商？他们会改变这些思路：

*quarters = *quarters + q;
coin_change = coin_change - 25;

进入这个：

*quarters += q;
coin_change -= 25;

修好这些东西后，你的代码运行正常。

Answer 2

我不想为你编写代码，因为这有点像家庭作业，但这是算法：

read_from_keyboard(amount_due)
read_from_keyboard(amount_paid)
change = amount_paid - amount_due

for each denomination in (
  fifties, twenties, tens, fives, ones, quarters, dimes, nickels, pennies) {

  while (change >= value of denomination) {
     increment counter for denomination
     subtract value of denomination from change
  }

  print counter + name of denomination  // Ex: "4 twenties"
}

“技巧”是要意识到你可以用完全相同的方式处理整个美元价值和硬币 - 编程艺术的一部分是能够找到一个可以重复使用的通用解决方案，而不是处理每种情况都是特例。

您可能希望将更改转换为表示以美分为单位的值的整数，因此可以避免浮点运算创建的舍入错误。

祝你好运！

我需要帮助让这个程序正确打印我的输出

2 个答案: