指针家庭作业

时间:2012-03-22 14:39:16

标签: c++ arrays pointers type-conversion

如果有人能帮助我完成这项工作,并指出必须采取哪些措施才能使该计划有效,那就太棒了。

- 用户想要从1-365进入的天数(验证)

- 每天在-60到90摄氏度之间的温度(循环,验证)

- 将每个值转换为华氏度(函数)

- 输出结果(功能)

问题

- 用户应输入一个int Celsius数字,一个整数,但它会转换为一个两倍的华氏数字 恩。 4摄氏度转换为39.20华氏度

  • 此代码......

    cout<< "摄氏温度为白天" << i + 1<< " :&#34 ;;

    *(天+ 1)= GetValidInt("",TEMP_MIN,TEMP_MAX);

它输出并等待新线路上的输入...如何让它等待同一线路上的输入?

    #include <IOSTREAM> // input/outout stream
    #include <IOMANIP>  // for setw manipulator
    #include <CFLOAT>   // for limits of a double DBL_MIN and DBL_MAX
    #include <CLIMITS>  // for limits of a int INT_MIN and INT_MAX

    using namespace std;

    //Function Prototypes
    double GetValidDouble(string prompt = "", const double MIN = DBL_MIN, const double MAX = DBL_MAX);
    int GetValidInt(string prompt = "", const int MIN = INT_MIN, const int MAX = INT_MAX);
    int outputFunc (int*);
    double calcCelsius(double*);
    int main() {
            //Constants
            const int TEMP_MIN = -90;
            const int TEMP_MAX = 60;
            const int DAYS_MIN = 1;
            const int DAYS_MAX = 365;
            //Pointer
            int numDays;
            int *days;
            //Determine the number of days to get input for
            //Validation - Must be numeric || Between 1 - 365
            numDays = GetValidInt("How many days do you wish to enter? ", DAYS_MIN, DAYS_MAX);

            //Array Allocation
            cout << "TEMPRETURE REPORTER" << endl;
            cout << "====================" << endl;
            cout << "Please enter the tempreture for each day." << endl;
            try{
                    days = new int[numDays];
                        for(int i = 0; i < numDays; i++){
                            cout << "Celsius temperature for Day " << i+1 << " : ";
                            *(days + 1) = GetValidInt("", TEMP_MIN, TEMP_MAX);
                            //Validation - Between -90.00C and 60.00C
                        }
                        //for loop
                        for(int i = 0; i < numDays; i++){
                                cout << "" << outputFunc(&days);
                              }
                        //output function
                    delete[] days;
                }
            catch(bad_alloc){
                    cout << "\nCould not allocate that amount memory.";
                }
            cout << endl << endl;
            system("pause");
            return 0;
            }
            //An inline function is a function upon which the compiler has been requested to perform inline expansion. 
            //In other words, the programmer has requested that the compiler insert the complete body of the function 
            //in every place that the function is called, rather than generating code to call the function in the one place it is defined.
            inline double calcCelsius(double* celsius){
                double fahrenheit = 0;
                fahrenheit = (celsius*9/5)+32;
                return fahrenheit;
            }
            //Output Function
            int outputFunc (int* days){
                double fahrenheit = 0;
                //PROCESS
                //double     //&days int
                fahrenheit = calcCelsius(&days); //Calling calcCelsius
                //OUTPUT
                cout << right << setw(15) << "Day " << numDays << setw(10) << fahrenheit << char(248) << "F" << setw(10) << numDays << char(248) << "C" << endl;
            }
            double GetValidDouble(string prompt, const double MIN, const double MAX){
               double validNumber = 0.0; // holds the user input
               string rubbish;           // holds garbage input.

               cout << endl << prompt << " "; 
               cin >> validNumber;       // try to get input
               if(cin.fail()){           // if user input fails...
                   cin.clear();              // reset the cin object
                   cin >> rubbish;           // cleans garbage from cin.

                   // report the problem to the user.
                   cerr << "\nInvalid input. Please try again and enter a numeric value.\n";
                   // Try again by calling the function again (recursion)
                   validNumber = GetValidDouble(prompt, MIN, MAX);
               } 
               else if(validNumber < MIN || validNumber > MAX){// if value is outside range...
                   // report the problem to the user.
                   cerr << "\nInvalid input. Please try again and enter a value between "
                        << MIN << " and " << MAX << ".\n";
                   // Try again by call the function again (recursion)
                   validNumber = GetValidDouble(prompt, MIN, MAX);
               }
               return validNumber; // returns a valid value to the calling function.
            }
            int GetValidInt(string prompt, const int MIN, const int MAX){
                   double validNumber = 0.0; // holds the user input
                   validNumber = GetValidDouble(prompt, MIN, MAX); // get a number
                   if((int) validNumber < validNumber) // if the value is not a whole number...
                   {
                       cerr << "\nInvalid input. Please try again and enter a whole number.\n";
                       // Try again by calling the function again (recursion)
                       validNumber = GetValidInt(prompt, MIN, MAX);
                   }
                   return (int) validNumber; // returns a valid value to the calling function.
            }

3 个答案:

答案 0 :(得分:1)

您在请求号码前输出换行符:

  cout << endl << prompt << " ";  // Output a line break ????
  cin >> validNumber;       // try to get i

只需删除上面的第一行。

答案 1 :(得分:1)

你的问题就在这一行:

cout << endl << prompt << " ";
getValidDouble中的

。它在从用户获取值之前输出换行符,之后输出您自己的提示。

为什么你实际上没有使用 prompt参数来询问什么?显然有一个原因: - )

这样,它将在换行符之后输出,您的输入将在同一行。换句话说,就像改变:

cout << "Celsius temperature for Day " << i+1 << " : ";
*(days + 1) = GetValidInt("", TEMP_MIN, TEMP_MAX);

成:

#include <sstream>
:
std::stringstream ss;
ss << "Celsius temperature for Day " << (i+1) << " : ";
*(days + 1) = GetValidInt (ss.str(), TEMP_MIN, TEMP_MAX);

这应该可以解决您的问题,提示后的换行符。您还有一些其他问题,例如将错误的数据类型传递给函数,但我会让它们为您修复,因为它会让您成为更好的程序员。一个提示,编译时带有警告,读取编译器告诉你的内容。

答案 2 :(得分:0)

尝试,我的意思是尝试,xcode没有标记任何错误,但没有时间运行它并调试它,这(显然它不完整,只是剪切和粘贴在你的上面)

    //Function Prototypes
double GetValidDouble(string prompt = "", const double MIN = DBL_MIN, const double MAX = DBL_MAX);
int GetValidInt(string prompt = "", const int MIN = INT_MIN, const int MAX = INT_MAX);
void outputFunc (int*,int);
double calcCelsius(double*);
int main() {
    //Constants
    const int TEMP_MIN = -90;
    const int TEMP_MAX = 60;
    const int DAYS_MIN = 1;
    const int DAYS_MAX = 365;
    //Pointer
    int numDays;
    int *days;
    //Determine the number of days to get input for
    numDays = GetValidInt("How many days do you wish to enter? ", DAYS_MIN, DAYS_MAX);  //Validation - Must be numeric || Between 1 - 365

    //Array Allocation
    cout << "TEMPRETURE REPORTER" << endl;
    cout << "====================" << endl;
    cout << "Please enter the tempreture for each day." << endl;
    try{
        days = new int[numDays];
        for(int i = 0; i < numDays; i++){
            string prompt = "Celsius temperature for Day "  + (i+1);
            *(days + 1) = GetValidInt(prompt, TEMP_MIN, TEMP_MAX); //Validation - Between TEMP_MIN and TEMP_MAX
        }
        //for loop
        for(int i = 1; i < numDays; i++){
            cout << "" ;
            outputFunc(days,i);  //we send the whole array
        }
        //output function
        delete[] days;
    }
    catch(bad_alloc){
        cout << "\nCould not allocate that amount memory.";
    }
    cout << endl << endl;
    system("pause");
    return 0;
}
//An inline function is a function upon which the compiler has been requested to perform inline expansion. 
//In other words, the programmer has requested that the compiler insert the complete body of the function 
//in every place that the function is called, rather than generating code to call the function in the one place it is defined.
inline double calcCelsius(int celsius){
    return (celsius*9/5)+32; //parentheses not really needed
}
//Output Function
void outputFunc (int* days, int a){
    int temp = days[a];
    cout << right << setw(15) << "Day " << a << setw(10) << calcCelsius(temp) << char(248) << "F" << setw(10) << &days << char(248) << "C" << endl;
}

我没有改变任何其他事情。我不知道这是否真的是你需要的,我的意思是它完成了工作(可能),或者至少它会有一些变化。但我不知道你是否应该特别使用任何东西。

主要变化:

  • outputFunc现在无效并且在其中有couts。你可以这样做或 让它返回一个std :: string并输出它。但你不能拥有它 返回一个int,并在其中输出(你可以,但它不是什么 你需要这里)。
  • newDay在outputFunc中脱离了上下文,所以你需要 通过它。但无论如何它是你需要发送的计数器。

  • calcCelcius(我将其命名为deg2far或celc2far)现在返回一个 double并采用int(仍为内联)

  • 请记住,您在i + 1中存储值(从0开始) 因此,您的第一个值是以天为单位[1] ...输出循环应该开始 在1。

可能还有其他一些变化(显然是funcs的原型),但那些是主要的。

我不确定第54行string prompt = "Celsius temperature for Day " + (i+1);是否可行,也许您需要单独声明它。