Question

该节目正在输出“女学生的平均GPA是：-1。＃IND”而不是它应该实际推出的。我的.dat文件格式如下：
f 2.4
f 2.6
3.5
等。我希望它输出这些值的平均GPA，但变量“avgfGPA”和“avgmGPA”最终为“-1。＃IND”

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

using namespace std;

void openFiles(ifstream& inFile, ofstream& outFile)
{
inFile.open("finalin.dat");
outFile.open("finalout.dat");
outFile << fixed << showpoint << setprecision(2);
inFile >> fixed >> showpoint >> setprecision(2);
if (!inFile||!outFile)
{
cout << "Problem opening file.";
}
}
void initialize(int &countFemale,int &countMale,float &sumFemaleGPA,float &sumMaleGPA)
{
countFemale=0;
countMale=0;
sumFemaleGPA=0;
sumMaleGPA=0;
}
void sumGrades(ifstream& inFile, float &sumFemaleGPA, float &sumMaleGPA,int &m,int &f)
{
sumFemaleGPA=0;
sumMaleGPA=0;

if (!inFile)
{
    inFile.open("finalin.dat");
}
char sex;
float grade;    

while(!inFile.eof())
{

inFile >> sex >> grade;

switch (sex)
{
case 'f': sumFemaleGPA= (sumFemaleGPA + grade);
     f++;
    break;
case 'm': sumMaleGPA= (sumMaleGPA + grade);
    m++; 
     break;
}
}
void averageGPA(float &avgfGPA, float &avgmGPA, int &m, int &f, float &sumFemaleGPA, float &sumMaleGPA)
{
avgmGPA=0;
avgfGPA=0;

avgfGPA=sumFemaleGPA/f;
avgmGPA=sumMaleGPA/m;
}

void printResults(float &avgfGPA, float &avgmGPA, ofstream& outFile)
{
    cout <<"The average GPA of the female students is: "<<  avgfGPA << endl;
    cout <<"The average GPA of the male students is: "<< avgmGPA;

    outFile << "The average GPA of the female students is: "<<  avgfGPA  << endl;
    outFile <<"The average GPA of the male students is: "<< avgmGPA;

}

    int main()
{

int countFemale;
int countMale;
float sumFemaleGPA;
float sumMaleGPA;
float avgfGPA; 
float avgmGPA;

ifstream inFile;
ofstream outFile;

openFiles(inFile,outFile);
initialize(countFemale,countMale,sumFemaleGPA,sumMaleGPA);
sumGrades(inFile,sumFemaleGPA,sumMaleGPA,countMale,countFemale);
averageGPA(avgfGPA,avgmGPA,countMale,countFemale,sumFemaleGPA,sumMaleGPA);
printResults(avgfGPA,avgmGPA, outFile);


}

Answer 1

您的问题是引用或缺少引用：

此代码：

void averageGPA（float avgfGPA，float avgmGPA，int m，int f，float   sumFemaleGPA，float sumMaleGPA）{avgmGPA = 0; avgfGPA = 0;

avgfGPA = sumFemaleGPA / F; avgmGPA = sumMaleGPA /米; }

应该是

...删除解决方案（作业）

更清楚一点，C ++与Java的不同之处在于，如果您希望它们在其他地方更改，则需要传递值by reference

获取奇怪的值来读取文本文件，获得无限值输出

1 个答案: