我正在尝试使calcCost函数现在可以正常工作。它不会继承area变量。任何想法为什么不起作用？我可以使用calcArea函数，但是可以将面积值用作calcCost面积值吗？我开始尝试在其中放置一个指针，但是我对它们还不十分了解。
#include <stdio.h>
#include <conio.h>
#include <stdlib.h>
// Define Constants
#define SALESTAX .07
#define TILEONE 0.78
#define TILETWO 1.59
#define TILETHREE 0.89
#define TILEONECASE 17.44
#define TILETWOCASE 10.89
#define TILETHREECASE 15.50
#define TILESIZE1 2.25
#define TILESIZE2 0.97222
#define TILESIZE3 1.77777
// Prototypes
void welcomeMessage(void);
char SelectChoice();
double getLength();
double getWidth();
double calcArea(double len, double wid);
double calcCost(double area);
void endMessage(void);
//integar return type, parameters are void,Richard's Flooring main function allows users to calculate room area and buy flooring.
int main (void)
{
//declare variables
double len, wid, area, tileNeeded,subTotal, taxTotal, total,cost;
double *dp;
char answer, myChoice;
dp = &area;
// Greets users and identifities program.
welcomeMessage ();
//Loop continues until user is done calculating area and buying flooring.
printf("Choice | Dimesions | Price | Sq.FT.per case|\n 1 | 18 x 18 | $%.2lf | 17.44 |\n 2 | 7 x 20 | $%.2lf | 10.89 |\n 3 | 16 x 16 | $%.2lf | 15.50 |\n",TILEONE, TILETWO, TILETHREE);
myChoice = SelectChoice();
len = getLength();
wid = getWidth();
// calcArea function is a double return type, it calculates the Area entered in by the user, its parameters are double len and double wid
area = calcArea(len,wid);
printf("The area of your room is: %g square feet.\n",area);
calcCost(area);
//Provides users with publisher's name.
endMessage ();
return 0;
}
// no return type, tells users what kind of program they are using, and voids any parameters.
void welcomeMessage (void)
{
printf("Welcome to Richard's Flooring\n");
system ("pause");
return ;
}
// no return type, allows user to select choice
char SelectChoice()
{
char myChoice;
do
{
printf("\nWhich tile choice would you like: ");
scanf(" %c", &myChoice);
switch(myChoice)
{
case '1':
printf("You chose choice: 1");
break;
case '2':
printf("You chose choice: 2");
break;
case '3':
printf("You chose choice: 3");
break;
default:
printf("\nINVALID CHOICE 1 - 3 only!");
}
}
while (myChoice > '3'|| myChoice < '1');
return myChoice;
}
double getLength()
{
double len;
// loop continues until positive numbers are entered.
do
{
printf("\nEnter length of room in feet: ");
scanf(" %lf", &len);
if (len <= 0)
printf("\nLength must be positive number.");
}
while (len <=0);
return len;
}
double getWidth()
{
double wid;
// loop continues until positive numbers are entered.
do
{
printf("\nEnter width of room in feet: ");
scanf(" %lf", &wid);
if (wid <= 0)
printf("\nWidth must be positive number.");
}
while (wid <=0);
return wid;
}
// Double return type, which is returning Area. Calculates the Area in a square or rectangle with the formula length * width. Accepts parameters from double len and double wid.
double calcArea(double len, double wid)
{
double area;
area = (len * wid);
return area;
}
double calcCost(double area)
{
SALESTAX ;
double len, wid, tileNeeded,subTotal, taxTotal, total,cost;
char answer, myChoice;
area = calcArea(len,wid);
do
{
char myChoice;
if (myChoice == '1')
{
tileNeeded = area/TILESIZE1;
}
else if (myChoice == '2')
{
tileNeeded = area/TILESIZE2;
}
else if (myChoice == '3')
{
tileNeeded = area/TILESIZE3;
}
printf("You will need %.2lf pieces of tile\n", tileNeeded);
subTotal = tileNeeded * TILETHREE;
printf("Your subtotal is: $%.2lf \n", subTotal);
taxTotal = subTotal * SALESTAX;
printf("Your sales tax comes out to be: $%.2lf \n", taxTotal);
total = taxTotal + subTotal;
printf("Your grand total is: $%.2lf \n",total);
printf("Would you like to measure another room?\n y or n:");
scanf(" %c", &answer);
}
while (answer == 'y'|| answer == 'Y');
}
// no return type, tells users Richard made the program, voids any parameters
void endMessage (void)
{
printf("\nThese results were provided by Richard Triplett\n");
system ("pause");
return ;
}
最佳答案
总的来说，您有以下几行代码来计算面积并将其传递给calcCost：
area = calcArea(len,wid);
printf("The area of your room is: %g square feet.\n",area);
calcCost(area);
这应该可以正常工作，但是在calcCost中，您可以：
double len, wid, tileNeeded,subTotal, taxTotal, total,cost;
char answer, myChoice;
area = calcArea(len,wid);
这将根据calcCost中定义的len和wid变量重新计算面积。这两个值从未设置为特定值，因此它们的值不确定，这导致整个区域不确定。
如果从calcCost中删除
area = calcArea(len,wid);行，则至少将使用正确的area值。您还将遇到myChoice的问题，因为再次在calcCost中重新定义了它的值，并且不确定的值。最简单的解决方案可能是使myChoice成为calcCost的附加参数，并将其从main传入。
calcCost中的do循环也无法按要求工作。每次按“ y”或“ Y”，它将返回完全相同的答案。 do循环可能应该迁移到main中，但是我现在才将其完全删除。
需要更改：
在主要
calcCost(area,myChoice);
在calcCost中
double calcCost(double area, char myChoice)
{
double tileNeeded,subTotal, taxTotal, total,cost;
if (myChoice == '1')
{
tileNeeded = area/TILESIZE1;
}
else if (myChoice == '2')
{
tileNeeded = area/TILESIZE2;
}
else if (myChoice == '3')
{
tileNeeded = area/TILESIZE3;
}
printf("You will need %.2lf pieces of tile\n", tileNeeded);
subTotal = tileNeeded * TILETHREE;
printf("Your subtotal is: $%.2lf \n", subTotal);
taxTotal = subTotal * SALESTAX;
printf("Your sales tax comes out to be: $%.2lf \n", taxTotal);
total = taxTotal + subTotal;
printf("Your grand total is: $%.2lf \n",total);
}
关于c - 我正在尝试将数据从calcArea函数传递给calcCost函数，但是我遇到了麻烦，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/35423132/