C++ Read and Writing Objects in Binary mode

I've been having some issues with the read() and write() functions in C++ for binary file handling of objects. I've been facing issues while reading and writing an Object to a file.

Here is the code. I've tried all kinds of little tweaks here and there, but none appear to have any effect.

#include <iostream>
#include <fstream>
using namespace std;


class Participant {
    int ID;
    string NAME;
    int SCORE;
    fstream file;

public:
    Participant(const Participant &p) {
        this->ID = p.ID;
        this->NAME = p.NAME;
        this->SCORE = p.SCORE;
    }
    Participant () {}
    Participant(int id, string name, int score) {
        ID = id;
        NAME = name;
        SCORE = score;
    }
    void input() {
        file.open("participant.dat", ios::app | ios::binary);
        file.write((char*)this, sizeof(*this));
        file.close();
    }

    void output(int id) {
        file.open("participant.dat", ios::in | ios::binary);
        Participant p;

        while(!file.eof()) {
            file.read((char*)&p, sizeof(p));

            if (p.ID == id) {
                cout << "Match Found" << endl;
                cout << "Name: " << p.NAME << endl;
                cout << "ID: " << p.ID << endl;
                cout << "Score: " << p.SCORE << endl;
                file.close();
                return;
            }
        }
        file.close();
    }
};

//fstream Participant::file;


int main() {
    fstream f;
    f.open("participant.dat", ios::out);
    f.close();

    Participant p1(1, "Sam", 200);
    Participant p2(2, "Bob", 100);
    p1.input();
    p2.input();
    p1.output(2);

    //Participant::output(1);
}

The output appears correctly, however, it crashes right afterwards. Through the use of "Cout" statements I was able to deduce that it crashes right after the output() method.

The error code my IDE (codeblocks) gives me, -1073740940 (0xC0000374).

If there's someone who knows what the problem is, and how to solve it, help would be greatly appreciated.

Update:

Thanks to some debugging, and some of the comments, I figured out the problem. You need to use character arrays instead of strings.