return;
      }

      while (true) {
        int q = c[j] + o[j];
        if (q < 0) {
          switchDirection();
          continue;
        }
        if (q == j + 1) {
          if (j == 0) {
            break;
          }
          s++;
          switchDirection();
          continue;
        }

        Collections.swap(list, j - c[j] + s, j - q + s);
        c[j] = q;