读取文本文件获得奇怪的值，获得无限的值输出

程序输出"女生的平均GPA为:-1"。#IND"，而不是它实际应该发布的内容。我的。dat文件的格式如下:2.4 f
2.6 f

3.5 m
等。我希望它输出这些值的平均GPA，但是变量"avgfGPA"answers"avgmGPA"的结果是"-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);

}