C - 从 function 返回浮点值并打印它们

Question

我不确定我在这里做错了什么，但这总是将最后的平均变量打印为 0。

我尝试了多种方法，这是我得到的最接近的平均值，没有错误或警告，我得到的警告是 68 总毛默认为 int，68 计数器默认为 int。

#include <stdio.h>

#include <stdlib.h>

float finalCalc();

int main(){

int yORn = 1;

float totalGross;
float counter = 0;
float commissionEarned;
float grossPay;
float overTime;
char employeeCode;

do{

counter++;


printf("Please enter employee code:\n");
scanf(" %c", &employeeCode);

float hoursWorked;
printf("Please enter the hours they worked:\n");
scanf("%f", &hoursWorked);

float hourlyWageRate;
printf("Please enter there hourly rate in œ:\n");
scanf("%f", &hourlyWageRate);

if(employeeCode == 's' || employeeCode == 'S'){
        printf("Please enter any commission they have earned in œ:\n");
        scanf("%f", &commissionEarned);}

if(employeeCode == 's' || employeeCode == 'S'){
        grossPay = (hoursWorked * hourlyWageRate) + commissionEarned;
        printf("Department: Sales\nEmployee Code: %c\nGross pay: œ%6.2f\n", employeeCode, grossPay);
}

else if(employeeCode == 'f' || employeeCode == 'F'){
        overTime = (hoursWorked - 35) * 1.5;
        grossPay = (hoursWorked + overTime) * hourlyWageRate;
        printf("Department: Factory\nEmployee Code: %c\nGross pay: œ%6.2f\n", employeeCode, 
grossPay);
}

else{
        grossPay = (hoursWorked * hourlyWageRate);
        printf("Department: Admin\nEmployee Code: %c\nGross pay: œ%6.2f\n", employeeCode, grossPay);
}

totalGross = totalGross + grossPay;
printf("Would you like to enter another employee? 1 for yes 2 for no\n");
scanf("%d", &yORn);

}while(yORn == 1);
float average = finalCalc(totalGross, counter);
printf("The total gross pay was: œ%6.2f\nThe average gross pay was: œ%0.2f", totalGross, average);

return 0;}

float finalCalc(totalGross, counter){
float averageGross = totalGross / counter;
return averageGross;
};

Answer 1

float finalCalc(totalGross, counter)将参数声明为 int。 在这种情况下，int/int 产生 0。声明为： float finalCalc(float totalGross, float counter)

开始时您还需要一个原型，否则编译器将假定参数为 int 并在调用 function 之前将您的浮点数转换为 int。

我建议打开编译器的警告。 大多数编译器会针对这些情况发出警告。

Answer 2

您的代码和使用编译器的方式有四个明显的问题：

1. 在开发过程中编译 C 程序时，应始终启用警告。 不幸的是，默认情况下通常不会启用警告。 如果您使用 gcc 您只需将选项-Wall添加到命令中。

2. 当您启用警告时，编译器会发出类似

   test.c: In function 'finalCalc': test.c:68:7: warning: type of 'totalGross' defaults to 'int' [-Wimplicit-int] float finalCalc(totalGross, counter) ^~~~~~~~~ test.c:68:7: warning: type of 'counter' defaults to 'int' [-Wimplicit-int]

   使用 integer 除法，您得到零而不是零和一之间的数字。

3. 变量计数器不应该是 integer 而不是浮点数吗？

4. 您需要检查scanf的返回值，以确保用户输入了正确类型的值。