sclass IntBuffer {
  int[] data;
  int size;
  
  *() {}
  *(int size) { if (size != 0) data = new int[size]; }
  
  void add(int i) {
    if (size >= l(data))
      data = resizeIntArray(data, max(1, l(data)*2));
    data[size++] = i;
  }
  
  int[] toArray() {
    ret size == 0 ? null : resizeIntArray(data, size);
  }
  
  void reset { size = 0; }
}