message: Update transform-to-chessboard.cpp
diff: @@ -68,7 +68,7 @@ private:
  int i = begin;
  int sum = 0;
  for (const auto& v : seq1) {
  - sum += (i - v + 2) % 2;
  + sum += static_cast<int>((i % 2) != v);
  ++i;
  }
  result = min(result, sum / 2);
  