explain the reverse in graph
base i rightmost less than n\n\n\n# base i rightmost greater than n\n\n\n\n\nso the rightmost index is min(i + k - 1, 2 * n - k - 1 - i)\n\n\n# same idea to get
# base i rightmost less than n\n![Screen Shot 2023-04-02 at 21.21.46.png](https://assets.leetcode.com/users/images/d34fd583-ee82-472c-a4ab-08cd24486aed_1680441774.540572.png)\n\n# base i rightmost greater than n\n\n![Screen Shot 2023-04-02 at 21.29.22.png](https://assets.leetcode.com/users/images/114d800b-c3bd-459b-86f3-dc42528a1236_1680442186.427925.png)\n\n```\nso the rightmost index is min(i + k - 1, 2 * n - k - 1 - i)\n```\n\n# same idea to get leftmost index\n\n\n
['Graph']