<p>You are given an <code>m x n</code> integer matrix <code>grid</code>​​​.</p>

<p>A <strong>rhombus sum</strong> is the sum of the elements that form <strong>the</strong> <strong>border</strong> of a regular rhombus shape in <code>grid</code>​​​. The rhombus must have the shape of a square rotated 45 degrees with each of the corners centered in a grid cell. Below is an image of four valid rhombus shapes with the corresponding colored cells that should be included in each <strong>rhombus sum</strong>:</p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/04/23/pc73-q4-desc-2.png" style="width: 385px; height: 385px;" />
<p>Note that the rhombus can have an area of 0, which is depicted by the purple rhombus in the bottom right corner.</p>

<p>Return <em>the biggest three <strong>distinct rhombus sums</strong> in the </em><code>grid</code><em> in <strong>descending order</strong></em><em>. If there are less than three distinct values, return all of them</em>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/04/23/pc73-q4-ex1.png" style="width: 360px; height: 361px;" />
<pre>
<strong>Input:</strong> grid = [[3,4,5,1,3],[3,3,4,2,3],[20,30,200,40,10],[1,5,5,4,1],[4,3,2,2,5]]
<strong>Output:</strong> [228,216,211]
<strong>Explanation:</strong> The rhombus shapes for the three biggest distinct rhombus sums are depicted above.
- Blue: 20 + 3 + 200 + 5 = 228
- Red: 200 + 2 + 10 + 4 = 216
- Green: 5 + 200 + 4 + 2 = 211
</pre>

<p><strong class="example">Example 2:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/04/23/pc73-q4-ex2.png" style="width: 217px; height: 217px;" />
<pre>
<strong>Input:</strong> grid = [[1,2,3],[4,5,6],[7,8,9]]
<strong>Output:</strong> [20,9,8]
<strong>Explanation:</strong> The rhombus shapes for the three biggest distinct rhombus sums are depicted above.
- Blue: 4 + 2 + 6 + 8 = 20
- Red: 9 (area 0 rhombus in the bottom right corner)
- Green: 8 (area 0 rhombus in the bottom middle)
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> grid = [[7,7,7]]
<strong>Output:</strong> [7]
<strong>Explanation:</strong> All three possible rhombus sums are the same, so return [7].
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>m == grid.length</code></li>
	<li><code>n == grid[i].length</code></li>
	<li><code>1 &lt;= m, n &lt;= 50</code></li>
	<li><code>1 &lt;= grid[i][j] &lt;= 10<sup>5</sup></code></li>
</ul>

class Solution:
    def getBiggestThree(self, grid: List[List[int]]) -> List[int]:
        m, n = len(grid), len(grid[0])
        def rhombsum(i, j, r):
            if r == 0:
                return grid[i][j]
            s = 0
            for a in range(r):
                x, y = r - a, a
                s += grid[i + x][j + y] + grid[i - y][j + x] + grid[i - x][j - y] + grid[i + y][j - x]
            return s
        ans = set()
        for i in range(m):
            for j in range(n):
                for r in range(min(i, j, m - i - 1, n - j - 1) + 1):
                    ans.add(rhombsum(i, j, r))
        return sorted(list(ans), reverse=True)[:3]
19900