올바르게 반복되지 않음

이 코드의 목적은 기본적인 도서관 체크인 체크 아웃 시스템이며, 스캐너를 사용하여 ISBN 번호 인 바코드를 입력 한 다음 프로그램이 내 .txt 데이터베이스를보고 도서 이름을 검색합니다. 그런 다음 책을 확인하고 싶은지 물어보고 학생 ID 번호를 묻고 ISBN, out / in, id 번호 및 현재 시간을 FILE로 출력합니다. 프로그램은 처음에는 훌륭하게 작동하지만 바코드를 입력 한 후 다른 책을 확인하려고하면 작동이 중지됩니다. 그것은 단지 정지에서 움직일 수없는 입력을 취하지 않을 것입니다.

#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
#include <ctime>
using namespace std;

int main()
{

char variable = 1;
ifstream infile;
ofstream outfile;
infile.open("Library_Database.txt");
outfile.open("Library_Checkout.txt", ios::app);

do {
    char variable;
    cout << "SETSUCON MANGA LIBRARY DATABASE\n\n" << setw(45) << "For Check-Out please enter: O or o\n" << setw(45) << "For Check-In please enter: I or i\n" << setw(45) << "For Assistance please enter: H or h\n" << setw(45) << "To close this program please enter: Q or q\n" << setw(50) << "Enter an option: ";
    cin >> variable;
    cout << "\n";

    if (variable == 'O' || variable == 'o'){

        double search;
        double ISBN = 0;
        string bookName;

        cout << "Please Scan Barcode: ";
        cin >> search; //runs fine one time then gets stuck here after I input the ISBN number the second time 

        while (ISBN != search){
            infile >> ISBN >> bookName;
        }
        cout << "You would like to check out: " << bookName << "?" << endl;

        string idNumber;
        char yesOrNo;
        cout << "Yes or No (Y or N): ";
        cin >> yesOrNo;
        if (yesOrNo == 'Y' || yesOrNo == 'y'){
            cout << "Please input Student ID number or Badge ID Number: ";
            cin >> idNumber;
            cout << endl;
            time_t now = time(0);
            char* dt = ctime(&now);

            outfile.setf(ios::fixed);
            outfile.precision(0);

            outfile << search << std::resetiosflags(std::ios::showbase) << setw(12) << idNumber << setw(4) << "out" << setw(30) << dt << endl;
        }
        else{
            cout << endl << "\n";
            continue;
        }
    }

    else if (variable == 'I' || variable == 'i'){

        double search;
        double ISBN = 0;
        string bookName;

        cout << "Please Scan Barcode: ";
        cin >> search; //runs fine one time then gets stuck here after I input the ISBN number the second time

        while (ISBN != search){
            infile >> ISBN >> bookName;
        }
        cout << "You would like to check in: " << bookName << "?" << endl;

        string idNumber;
        char yesOrNo;
        cout << "Yes or No (Y or N): ";
        cin >> yesOrNo;
        if (yesOrNo == 'Y' || yesOrNo == 'y'){
            cout << "Please input Student ID number or Badge ID Number: ";
            cin >> idNumber;
            cout << endl;
            time_t now = time(0);
            char* dt = ctime(&now);

            outfile.setf(ios::fixed);
            outfile.precision(0);

            outfile << search << std::resetiosflags(std::ios::showbase) << setw(12) << idNumber << setw(4) << "in" << setw(30) << dt << endl;
        }
        else{
            cout << endl << "\n";
            continue;
        }
    }
    else if (variable == 'H' || variable == 'h'){
        cout << "This program was written Shea Transue.\n" << "For Assistance Please Contact Shea Transue at 484-264-5863\n\n";
    }
    else if (variable == 'Q' || variable == 'q') {
        cout << "Thank you for using the SETSUCON LIBRARY DATABASE.\n" << "For assistance please Call or Text Shea Transue at 484-264-5864\n\n";
        break;
    }
    else {
        cout << variable << " is not a valid option. Try again\n\n";
    }

} while (variable != 'Q' || variable != 'q');

infile.close();
outfile.close();
return 0;
}