No Instance of Overloaded function while using STL queues - c++

Question

Okay so I have a programming project due in about 7 minutes. My project reads a double GPA and a string Name in a txt file. I correctly place the GPA and Names into separate STL lists for the project. My problem comes when I try to push the highest GPA value into a queue. At that point it gives the error that no instance of overloaded function.
Since I am using pointers, I have tried different methods of using pointers but to no avail. I figure that pointers might be a part of the problem.
#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
#include <list>
#include <queue>
using namespace std;
//using std::because it says cout is ambiguous even with std included
int main()
{
double GPA;
double highestGPA;
string name;
list<double> listGPA; //lists and their iterators
//list<double>::iterator ptrGPA, ptrHighestGPA;
double *ptrGPA, *ptrHighestGPA;
list<string> listName;
//list<string>::iterator ptrName, ptrHighestName;
string *ptrName, *ptrHighestName;
queue<double> queueGPA; //queues
//queueGPA.front() = 0;
queue<string> queueName;
//queueName.front() = "";
ifstream infile;
infile.open("HighestGPAData.txt");
if (!infile) //if file doenst exist
{
std::cout << "The input file does not "
<< "exist. Program terminates!"
<< endl;
std::system("pause");
return 1;
}
std::cout << fixed << showpoint;
std::cout << setprecision(2);
infile >> GPA >> name;
while (infile) { //place contents of file into 2 STL lists
listGPA.push_back(GPA);
listName.push_back(name);
infile >> GPA >> name;
}
std::cout << "\nSTL list for GPA:\n";
for (auto g : listGPA) { //range based for loop that prints GPA list
std::cout << g << "\n";
}
std::cout << "\nSTL list for names:\n";
for (auto s : listName) { //range based for loop that prints name
std::cout << s << "\n";
}
std::system("pause");
ptrGPA = &listGPA.front(); //initialize pointers for each list
ptrHighestGPA = ptrGPA;
ptrName = &listName.front();
ptrHighestName = ptrName;
while (!listGPA.empty()) // there are two lists (name and GPA)
if (ptrGPA > ptrHighestGPA) {
while (!queueGPA.empty()) { //destroy queue i (so a lower
queueGPA.pop();
}
while (!queueName.empty()) { //destroy queue if a higher //gpa is found (so a lower gpa is not printed)
queueName.pop();
}
/***********************problem here */
ptrHighestGPA = ptrGPA;
queueGPA.push(ptrHighestGPA); //add to queue if it is
ptrHighestName = ptrName;
queueName.push(ptrHighestName);
}
else if (ptrGPA == ptrHighestGPA) { //add to the queue ifcurrent gpa
queueGPA.push(ptrHighestGPA);
queueName.push(ptrHighestName);
}
/* end problem */
listGPA.pop_front();
listName.pop_front();
ptrGPA++;
ptrName++; //= listName.front();
}
while (!queueGPA.empty()) { //print the largest gpa.
std::cout << queueGPA.front() << " ";
queueGPA.pop();
}
std::cout << "\n";
while (!queueName.empty()) { //print who has the highest gpa
std::cout << queueName.front() << " ";
queueName.pop();
}
std::system("pause");
return 0;
}
Currently it outputs both lists but I can easily comment that out. I want the queues queueName and queueGPA to contain the highest GPA and name associated with that GPA from the lists listGPA and listName.
Thank you guys