Вывод структуры в файл повторно

Сначала я ввожу все позиции структуры и они заносятся в файл, но если я захочу ввести повторно, предыдущий результат стирается и заменяется новым. Как сделать, что бы я запускал много раз программу и данные в файле не стирались?

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <locale.h>
#include <iostream>
#include <string>
#include <windows.h>
#include <fstream> 
using namespace std;
int main() {
setlocale(LC_ALL, "rus");
FILE* file;
struct company {
    char name[20];
    char www[20];
    char address[20];
    int index;
    char country[20];
    char region[20];
    char rayon[20];
    char city[20];
    char street[20];
    char house[20];
    char flat[20];
    int time;
    int employees;
    int filial;
};
struct company companies[14];
char i = 0;

for (int i = 0; i < 1; ++i)
{
    cout << "Enter name :" << endl;
    cin >> companies[i].name;
    cout << "Enter www:" << endl;
    cin >> companies[i].www;
    cout << "Enter address :" << endl;
    cin >> companies[i].address;
    cout << "Enter index :" << endl;
    cin >> companies[i].index;
    cout << "Enter country :" << endl;
    cin >> companies[i].country;
    cout << "Enter region :" << endl;
    cin >> companies[i].region;
    cout << "Enter rayon :" << endl;
    cin >> companies[i].rayon;
    cout << "Enter city :" << endl;
    cin >> companies[i].city;
    cout << "Enter street :" << endl;
    cin >> companies[i].street;
    cout << "Enter house :" << endl;
    cin >> companies[i].house;
    cout << "Enter flat :" << endl;
    cin >> companies[i].flat;
    cout << "Enter time :" << endl;
    cin >> companies[i].time;
    cout << "Enter empl :" << endl;
    cin >> companies[i].employees;
    cout << "Enter filial :" << endl;
    cin >> companies[i].filial;
    
}
ofstream outfile;
outfile.open("mkr.txt");
for (int i = 0; i < 1; ++i)
    outfile << companies[i].name << " " << companies[i].www << " " << companies[i].address << " " << companies[i].index << " "
    << companies[i].country << " " << companies[i].region << " " << companies[i].rayon << " " << companies[i].city << " "
    << companies[i].street << " " << companies[i].house << " " << companies[i].flat << " " << companies[i].time << " "
    << companies[i].employees << " " << companies[i].filial << endl;