C-Plus-Plus/data_structures/test_stack_students.cpp

/*
 * This program reads a data file consisting of students' GPAs
 * followed by their names. The program then prints the highest
 * GPA and the names of the students with the highest GPA.
 * It uses stack to store the names of the students
 * Run:
 *     make all
 *     ./main student.txt
 ************************************************************
 * */
#include <cassert>      // for assert
#include <cmath>        // for NAN
#include <fstream>      // for basic_ostream, basic_ifstream, basic_istream
#include <iomanip>      // for operator<<, setprecision, _Setprecision
#include <iostream>     // for cout
#include <string>       // for char_traits, operator>>, basic_string, operat...
#include <memory>       // for operator==

#include "./stack.hpp"  // for stack

int main(int argc, char* argv[]) {
    double GPA = NAN;
    double highestGPA = NAN;
    std::string name;

    assert(argc == 2);
    std::ifstream infile;
    stack<std::string> stk;

    infile.open(argv[1]);
    std::cout << std::fixed << std::showpoint;
    std::cout << std::setprecision(2);
    infile >> GPA >> name;
    highestGPA = GPA;

    while (infile) {
        if (GPA > highestGPA) {
            stk.clear();
            stk.push(name);
            highestGPA = GPA;
        } else if (GPA == highestGPA) {
            stk.push(name);
        }
        infile >> GPA >> name;
    }
    std::cout << "Highest GPA: " << highestGPA << std::endl;
    std::cout << "Students the highest GPA are: " << std::endl;
    while (!stk.isEmptyStack()) {
        std::cout << stk.top() << std::endl;
        stk.pop();
    }
    std::cout << std::endl;
    return 0;
}