目前我在C ++课程中，正在学习函数。我们的任务是创建一个程序来计算总成本，包括每个房间的每平方英尺的价格，人工和税收，由用户的计数输入给出。这是我的程序，我无法编译，我不知道为什么。感谢任何帮助我的人，我非常感谢。
例如，输入： 2 2 2 2 2 2 2
应该给出输出： 2 2 22.4
但它正在打印这个：
2 2 9.87
我不知道出了什么问题。我看了我所有的公式，看起来都很正确。一个尺寸为2 * 2的房间，每平方英尺2的成本，应该总成本为11.2，我很困惑。也许我错误地设置了这些功能？
#include <iostream>
#include <iomanip>
using namespace std;
void getdata (int&, int&, float&);
float InstalledPrice (int , int, float );
float totalprice (float);
void printdata (int , int, float);
int length, width, count, x;
float installation, costpersqfoot, price;
int main()
{
cout << "Enter the amount of rooms.\n";
cin >> x;
for(count = x; count != 0; count --)
{
getdata (length, width, costpersqfoot);
InstalledPrice (length, width, costpersqfoot);
totalprice (installation);
if (count ==1)
{
printdata (length, width, price);
}
}
}
void getdata(int & length, int & width, float & costpersqft)
{
cin >> length >> width >> costpersqft;
}
float InstalledPrice (int a, int b, float c)
{
installation = 0;
const float LABOR_COST = 0.35;
float sqfoot;
sqfoot = length * width;
installation = (costpersqfoot * sqfoot) + (LABOR_COST * sqfoot) + installation;
}
float totalprice(float installation)
{
const float TAX_RATE = 0.05;
price = (installation * TAX_RATE) + installation;
}
void printdata(int length, int width, float price)
{
cout << length << " " << width << " " << price << endl;
}
答案 0 :(得分：0)
在功能中
float InstalledPrice (int a, int b, float c)
每次执行该功能时都要重置安装值。
installation = 0;
尝试删除该行并将其插入主函数中的for循环之前。
installation = 0;
for(count = x; count != 0; count --)
使用代码中的常量，它将打印19.74
（（4 * 2）+（4 * 0.35）=每个房间9.4，两个房间18.8。含税，（18.8 * 1.05）= 19.74）`
答案 1 :(得分：0)
这里发生了很多事情，其中最重要的是解决函数的返回值，如@john所说。仅就您的数学而言，考虑1个2英尺x 2英尺的房间，每平方英尺2个成本 - 您的安装价格为installation = (2 * 4) + (.35 * 4) + 0，即9.4。稍后在您的计划中，您添加税，
price = 9.4 * .05 + 9.4，它给你9.87。不确定你提到的11.2来自哪里。
答案 2 :(得分：0)
如果你从函数的末尾开始返回除了void之外的其他东西，那么程序就会有未定义的行为，即它可以做任何想做的事情。产生除预期之外的其他产出是可以采取的最温和形式。
以下是您应该对代码进行的更改：
return语句（main()是一个例外，它不会绝对需要return，尽管它返回int但是仍然使用return 0;）是一种很好的风格。您应该验证所有输入实际上是否成功，例如，使用以下内容：
if (std::cin >> length >> width >> costpersquarefeet) {
// process the entered data
}
else {
std::cerr << "ERROR: failed to read inoyt!\n";
}
我可能会使用更详细的chrck，并告诉用户我期待的输入。
static变量并以某种方式访问它们;您可以在必要时了解全局变量，这可能是在将来的某个时期。）答案 3 :(得分：0)
#include <iostream>
#include <time.h>
#include <stdlib.h>
// This program is writen by KHUMBELO DIFFERENCE MUTHAVHINE from Ha- Vhangani . Khumbelo is a programmer
using namespace std;
// call function calculateCarpetSize
void CalculateCarpetSize (int &length, int &width, int &carpetSize)
{
carpetSize = length * width;
}
// call function calculateCarpetCost
void CalculateCarpetCost (int &carpetSize , float &sellingPrice , float &carpetCost )
{
float tax = 0.14;
carpetCost = carpetSize * sellingPrice * tax;
}
// call function calculateLabourCost
CalculateLabourCost(int &carpetSize , int &labour, float &labourCost)
{
labourCost = carpetSize * labour;
}
bool qualifyForDiscount(int &customerNo){
if (customerNo <=9999)
{
void computeDiscount (float &carpetCost );
return true ;
}
else{return false;
}
}
// call function computeDiscount
void computeDiscount (float &carpetCost, float &discountPercentage )
{
cout << "Enter the percetage discout: "<< endl;
cin >> discountPercentage ;
carpetCost = carpetCost * discountPercentage;
}
// call function printCustomerStatement
void printCustomerStatement( )
{
cout.setf(ios::fixed);
cout << endl;
cout << "CROSWELL CARPET STORE" << endl;
cout << "STATEMENT" << endl;
}
int main()
{
int customerNo;
string customerName, customersurname;
float roomLength;
float roomWidth, discountPercentage;
float sellingPrice;
float carpetCost;
float labourCost;
float discount;
int carpetSize;
int rooLength, roonWidth;
int labour = 24;
//float labourCost;
cout.setf(ios::fixed);
cout.precision(2);
cout << "\nPlease enter the following information: ";
cout << "\n Customer FIRST name: ";
cin >> customerName;
cout << "\n Customer LAST name: ";
cin >> customersurname;
cout << "\n Customer number: ";
cin >> customerNo;
cout << "\n The length of the room: ";
cin >> roomLength;
cout << "\n The width of the room: ";
cin >> roomWidth;
cout << "\n The carpet selling price: ";
cin >> sellingPrice;
// call function calculateCarpetSize
CalculateCarpetSize (rooLength, roonWidth, carpetSize);
// call function calculateCarpetCost
CalculateCarpetCost (carpetSize ,sellingPrice, carpetCost );
// call function calculateLabourCost
CalculateLabourCost(carpetSize , labour, labourCost);
if (customerNo<= 9999){
bool qualityForDiscout(customerNo);
computeDiscount (carpetCost, discountPercentage );
}
// call function computeDiscount
// call function printCustomerStatement
// printCustomerStatement(customerName, customerNo, carpetCost, labourCost, discount);
printCustomerStatement();
cout << "\n Customer name: ";
cout << customerName << customersurname<<endl;
cout << "\n Customer number: ";
cout << customerNo <<endl;
cout << "\n The length of the room: ";
cout << roomLength <<endl;
cout << "\n The width of the room: ";
cout<< roomWidth <<endl;
cout << "\n The carpet selling price: ";
cout<< "sellingPrice:" << sellingPrice <<endl;
return 0;
} // end main