LeetCode: Reshape the Matrix Solution

Approach

Steps:

• init new matrix
• flatten the input matrix, and reverse it
• pop each of the reversed flatten matrix into each of the new matrix element

Implementation

1/**
2 * @param {number[][]} mat
3 * @param {number} r
4 * @param {number} c
5 * @return {number[][]}
6 */
7var matrixReshape = function (mat, r, c) {
8  const [m, n] = [mat.length, mat[0].length]
9
10  if (m * n !== r * c) {
11    return mat
12  }
13
14  const newMatrix = Array.from({ length: r }, _ => Array(c))
15  const reversedFlattenMatrix = mat.flat().reverse()
16
17  for (let row = 0; row < r; row++) {
18    for (let col = 0; col < c; col++) {
19      newMatrix[row][col] = reversedFlattenMatrix.pop()
20    }
21  }
22
23  return newMatrix
24}