#include <vector>
#include <iostream>
#include "student_info.h"
#include "grade.h"
#include "approval.h"

bool fgrade(const StudentInfo& s) {
	return grade(s) < 60;
}

std::list<StudentInfo>
extract_fails(
	std::list<StudentInfo>& students)
{
	std::list<StudentInfo> fail;
	std::list<StudentInfo>::iterator iter = students.begin();

	while (iter != students.end()) {
		if (fgrade(*iter)) {
			fail.push_back(*iter);
			iter = students.erase(iter);
		} else {
			iter++;
		}
	}

	return fail;
}