函数中的参数太少而无法调用 [C 程序]

Question

所以，明天晚上我的在线 C 编程课程的作业要交了，我现在的编码有些问题。我已经把代码带给了我的老师，但她似乎不明白她是花钱教我的，而不是告诉我我的代码有问题。如果有人可以查看代码并帮助我修复它，我将不胜感激。代码位于下方。调用 printtripSummary 时出现错误的位置在 main 中。

#include <stdio.h>


void welcomeMessage();
void askuserForInput();
void printtripSummary(float avgMiles, float minCost, float maxCost, float travelMiles);

int main()
{
    /* Call the functions */
    welcomeMessage();
    askuserForInput();
    printtripSummary();
    printf("\nThank you, please drive safely and have a nice trip!\n");
    return 0;
}


void welcomeMessage()
{
    printf("Welcome to the Trip Planner!\n");
    printf("So you are ready to take a trip? Let me help you plan for\n");
    printf("your fuels costs and required stops to fill up your tank.\n");
    printf("============================================================\n");
    printf("Please provide answers to the prompts below and I will\n");
    printf("display a summary for you when I have computed the results.\n");
    printf("============================================================\n");
}
void askuserForInput()
{
    float avgMiles, minCost, maxCost, travelMiles;
    do{
        printf("Please input your car's average miles per gallon (enter 0 to quit)>> ");
        scanf_s("%f", &avgMiles);
        if (avgMiles == 0)
            break;
        printf("Please tell me the range of fuel costs you expect to pay (per gallon>>)\n");

        printf("The lowest per gallon cost of fuel is>> ");
        scanf_s("%f", &minCost);
        printf("The highest per gallon cost of fuel is>> ");
        scanf_s("%f", &maxCost);
        printf("Please tell me how many miles you plan to travel>> ");
        scanf_s("%f", &travelMiles);
        printtripSummary(avgMiles, minCost, maxCost, travelMiles);
    } while (avgMiles != 0);
}

void printtripSummary(float avgMiles, float minCost, float maxCost, float travelMiles)
{
    float avgGal, mingasPrice, maxgasPrice;
    do{
        avgGal = travelMiles / avgMiles;
        mingasPrice = avgGal * minCost;
        maxgasPrice = avgGal * maxCost;
        printf("You will be required to purchase %.2f gallons of fuel.\n", avgGal);
        printf("The price will range between %2f and $%.2f.\n", mingasPrice, maxgasPrice);
    } while (avgMiles != 0);
}

Answer 1

像这样（第 13 行）注释掉 main 中的函数调用：

//printtripSummary();

因为您已经在 askuserForInput(); 中调用了该函数，而该函数在 main 中被调用

或者如果你想在 main 中调用函数，你必须传递所需的参数，这些参数是：

(float avgMiles, float minCost, float maxCost, float travelMiles)

此外，您在函数 printtripSummary(); 中有一个无限循环，因为您有一个 do...while 循环来检查 avgMiles != 0，但由于您没有在此循环中更改 avgMiles 的值，所以它是无限循环的！

Answer 2

在第 13 行，您调用了 printtripSummary 函数，但没有向它传递任何参数。您必须提供函数定义指定的 4 个参数（avgMiles、minCost、maxCost、travelMiles）。