import 'dart:async';
import 'dart:io';
import 'dart:convert';

Stream<String> get lineStream =>
    stdin.transform(utf8.decoder).transform(const LineSplitter());

Future<List<String>> readLines() async {
  final lines = <String>[];
  await for (var line in lineStream) {
    lines.add(line);
  }
  return lines;
}

void main() async {
  final lines = await readLines();
  final nxt = lines[0].split(' ').map((e) => int.parse(e)).toList();
  var count = 0;
  var time = 0;
  while (nxt[0] > count) {
    count += nxt[1];
    time += nxt[2];
  }
  print(time);
}
