Question

初学者程序员，对所有程序员都非常尊重。我的头发已经消失了，有时我会因为试图解决这些问题而感到疲惫不堪。 Anyhoot当前分配让我从.txt文件读取数据，我已经完成了。执行计算并输出到屏幕。读入数据的变量多于我应该写入输出文件的变量。所以我读了数据，现在我必须将tripNumber和FinalCost读入两个不同的数组，然后将数据反向写入文件。我已经掌握了大部分内容，但我遇到了几个应该在我的代码中清楚的地方。意识到每个人都有自己的问题，这不是一个悲伤的故事。我每周工作60多个小时，正在努力获得学位。感谢您提供任何帮助或建议，使这项复杂的技能更容易理解。

#include <iostream>
#include <iomanip>
#include <string>
#include <fstream>

using namespace std;
int main()
{

//create two arrays
const int ARRAY_SIZE = 100; //array size of 100 elements

ifstream fileIn; //create file object 
ofstream fileSave; //create new output file
fileIn.open("TripInput.txt"); //read in file

//Variables to hold data from the file
int tripNbr = 0;
double fuelCost = 0;
double fuelTotal = 0;
double wasteDisp = 0;
double misCost = 0;

int counter = 0;

int nbrOfTrip[ARRAY_SIZE];
double totalCost[ARRAY_SIZE];

for(counter = 0; counter < ARRAY_SIZE; counter++)
{
nbrOfTrip[counter] = 0;
totalCost[counter] = 0;
}

cout<<"Welcome to My Space Travel Company"<<endl;
cout<<endl;
cout<<"Trip No"<<setw(10)<<"Fuel"<<setw(10)<<"Waste"<<setw(10)<<"Misc"<<setw(15)
<<"Discount Fuel"<<setw(15)<<"Final Cost"<<endl;

if(fileIn.fail())//test to see if file opened
{
cout<<"File did not open."<<endl;
}

while(fileIn>>tripNbr>>fuelCost>>wasteDisp>>misCost) //while loop to read in data from   file
{
fuelTotal = fuelCost - (fuelCost * .10);
double finalCost = fuelTotal + wasteDisp + misCost;
cout<<tripNbr<<setprecision(2)<<fixed<<setw(14)<<fuelCost<<setw(10)<<wasteDisp
    <<setw(10)<<misCost<<setw(15)<<fuelTotal<<setw(15)<<finalCost<<endl;

//Write trip number and final cost to the 2 parallel arrays...not sure how to
//to do this.


//open output file
fileSave.open("TripCost.txt");

//for loops to output data to file
for(counter = 0; counter < ARRAY_SIZE; counter++)
{
fileSave<< nbrOfTrip[counter]<<endl;
fileSave<< totalCost[counter]<<endl;
}
}
system("Pause");
return 0;
}

Answer 1

我发生了一些事情。首先你的'while循环来读取文件中的数据'在错误的地方结束。它应该是

while(fileIn>>tripNbr>>fuelCost>>wasteDisp>>misCost) //while loop to read in data from   file
{
    fuelTotal = fuelCost - (fuelCost * .10);
    double finalCost = fuelTotal + wasteDisp + misCost;
    cout<<tripNbr<<setprecision(2)<<fixed<<setw(14)<<fuelCost<<setw(10)<<wasteDisp
        <<setw(10)<<misCost<<setw(15)<<fuelTotal<<setw(15)<<finalCost<<endl;

    //Write trip number and final cost to the 2 parallel arrays...not sure how to
    //to do this.

}

输出到文件后，此循环结束。这意味着您将多次输出文件，这是不对的。

其次，将行程编号和最终成本写入阵列非常简单。您只需要一个额外的变量来计算您添加的行程数。我称之为'numberOfTrips'。喜欢这个

int numberOfTrips = 0;
while(fileIn>>tripNbr>>fuelCost>>wasteDisp>>misCost) //while loop to read in data from   file
{
    fuelTotal = fuelCost - (fuelCost * .10);
    double finalCost = fuelTotal + wasteDisp + misCost;
    cout<<tripNbr<<setprecision(2)<<fixed<<setw(14)<<fuelCost<<setw(10)<<wasteDisp
        <<setw(10)<<misCost<<setw(15)<<fuelTotal<<setw(15)<<finalCost<<endl;

    //Write trip number and final cost to the 2 parallel arrays
    nbrOfTrip[numberOfTrips] = tripNbr;
    totalCost[numberOfTrips] = finalCost;
    ++numberOfTrips;
}

最后，当您将数据写入文件时，您应该只写入添加到并行数组的条目数，而不是整个数组。所以最后一个循环应该使用前一个循环中的'numberOfTrips'变量。喜欢这个

//for loops to output data to file
for(counter = 0; counter < numberOfTrips; counter++)
{
    fileSave<< nbrOfTrip[counter]<<endl;
    fileSave<< totalCost[counter]<<endl;
}

具有并行数组的初学者编程学生

1 个答案: