Test 2 Q4 walkthrough with comments!

Q4:

#include <iostream>

#include <fstream>

#include <cstring>

using namespace std;

struct PhRec{

  char name[60];

  int PhoneNumber;

};

bool operator<(PhRec& left, PhRec& right){

  return strcmp(left.name, right.name) < 0;

}

#include "tqueue.h"

int main(){

  fstream f("phones.bin", ios::in|ios::binary);//just reads the file

  PhRec pr;

  Tqueue<PhRec> Q;//change all Tqueue type into PhRec type

  while(f.good()){//continue in this loop if f.good() is true

    f.read((char*)&pr, sizeof(pr));//reads the sizeof(pr) and store it in &pr as a char*

    if(f.good()){//if the previous read function worked go in here

      Q.append(pr);//append pr (in this case is a character string) to the queue list

    }

  }

  f.close();

  f.open("phones.bin", ios::out|ios::binary);//rewriting the file

  Q.sort(true);//sort the Queue list

  while(!Q.isEmpty()){//continue this loop until the Queue list is empty

    pr = Q.remove();//assign pr with the value of Q.remove();

    f.write((const char*)&pr, sizeof(pr));//write sizeof(pr) bytes from &pr as a char*

  }

  return 0;

}