readInput function
Implementation
String readInput() {
String? line;
do {
line = stdin.readLineSync(encoding: utf8);
if (line == null) {
print('Line is empty. Plz try again!');
} else {
line = line.trim();
}
} while (line == null || line.isEmpty);
if (line.toLowerCase() == 'q') {
exit(0);
}
return line;
}