SameProb2

public String returnOneLine(String filename) throws IOException {
  BufferedReader br = new BufferedReader(new FileReader(filename));
  
  String result = br.readLine();
  String tmp = null;
  int size = 2;
  while ((tmp = br.readLine()) != null) {
    int i = (int)(Math.random() * size++);
    if (i < 1) {
      result = tmp;
    }
  }
  br.close();
  return result;
}