<p>In MATLAB, there is a handy function called <code>reshape</code> which can reshape an <code>m x n</code> matrix into a new one with a different size <code>r x c</code> keeping its original data.</p>

<p>You are given an <code>m x n</code> matrix <code>mat</code> and two integers <code>r</code> and <code>c</code> representing the number of rows and the number of columns of the wanted reshaped matrix.</p>

<p>The reshaped matrix should be filled with all the elements of the original matrix in the same row-traversing order as they were.</p>

<p>If the <code>reshape</code> operation with given parameters is possible and legal, output the new reshaped matrix; Otherwise, output the original matrix.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/04/24/reshape1-grid.jpg" style="width: 613px; height: 173px;" />
<pre>
<strong>Input:</strong> mat = [[1,2],[3,4]], r = 1, c = 4
<strong>Output:</strong> [[1,2,3,4]]
</pre>

<p><strong class="example">Example 2:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/04/24/reshape2-grid.jpg" style="width: 453px; height: 173px;" />
<pre>
<strong>Input:</strong> mat = [[1,2],[3,4]], r = 2, c = 4
<strong>Output:</strong> [[1,2],[3,4]]
</pre>

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

<ul>
	<li><code>m == mat.length</code></li>
	<li><code>n == mat[i].length</code></li>
	<li><code>1 &lt;= m, n &lt;= 100</code></li>
	<li><code>-1000 &lt;= mat[i][j] &lt;= 1000</code></li>
	<li><code>1 &lt;= r, c &lt;= 300</code></li>
</ul>

class Solution:
    def matrixReshape(self, mat: List[List[int]], r: int, c: int) -> List[List[int]]:
        m = len(mat) # corresponds to y and r
        n = len(mat[0]) # corresponds to x and c

        if r*c != m*n:
            return mat
        
        res = [[0 for i in range(c)] for j in range(r)]

        for j in range(m):
            for i in range(n):
                y = (j*n + i)//c
                x = (j*n + i)%c
                res[y][x] = mat[j][i]
        return res
                

17300