A cell `(r, c)` of an excel sheet is represented as a string `"<col><row>"` where:

- `<col>` denotes the column number `c` of the cell. It is represented by alphabetical letters.
  - For example, the `1st` column is denoted by `'A'`, the `2nd` by `'B'`, the `3rd` by `'C'`, and so on.
- `<row>` is the row number `r` of the cell. The `rth` row is represented by the integer `r`.

You are given a string `s` in the format `"<col1><row1>:<col2><row2>"`, where `<col1>` represents the column `c1`, `<row1>` represents the row `r1`, `<col2>` represents the column `c2`, and `<row2>` represents the row `r2`, such that `r1 <= r2` and `c1 <= c2`.

Return the list of cells `(x, y)` such that `r1 <= x <= r2` and `c1 <= y <= c2`. The cells should be represented as strings in the format mentioned above and be sorted in non-decreasing order first by columns and then by rows.

Example 1:

    Input: s = "K1:L2"
    Output: ["K1","K2","L1","L2"]
    Explanation:
    The above diagram shows the cells which should be present in the list.
    The red arrows denote the order in which the cells should be presented.

Example 2:

    Input: s = "A1:F1"
    Output: ["A1","B1","C1","D1","E1","F1"]
    Explanation:
    The above diagram shows the cells which should be present in the list.
    The red arrow denotes the order in which the cells should be presented.

Constraints:

- `s.length == 5`
- `'A' <= s[0] <= s[3] <= 'Z'`
- `'1' <= s[1] <= s[4] <= '9'`
- `s` consists of uppercase English letters, digits and `':'`.