defibirilator

import 'dart:io';
import 'dart:math';

double toRadian(degree) => PI * degree / 180;
double parseDouble(string) => double.parse(string.replaceAll(',','.')); 

void main() {
    List<double> userLocation = new List<double>.generate(2, (index) => PI * double.parse(stdin.readLineSync().replaceAll(',','.')) / 180);
    List defibrillators = new List
                            .generate(int.parse(stdin.readLineSync()), (index) => stdin.readLineSync().split(';'))
                            ..forEach((defibrillator) => defibrillator.add(distance(userLocation, defibrillator)));
    defibrillators.sort((d1, d2) => d1[6].compareTo(d2[6]));
    print(defibrillators[0][1]);
}

double distance(user, defibrillator) {
    double longitude = toRadian(parseDouble(defibrillator[4]));
    double latitude = toRadian(parseDouble(defibrillator[5]));
    double x = (user[0] - longitude) * cos((user[1] + latitude) / 2);
    double y = (user[1] - latitude);
    return sqrt(x * x + y * y) * 6371;
}