0867. Transpose Matrix

https://leetcode.com/problems/transpose-matrix

Description

Given a 2D integer array matrix, return the transpose of matrix.

The transpose of a matrix is the matrix flipped over its main diagonal, switching the matrix's row and column indices.

Example 1:

**Input:** matrix = [[1,2,3],[4,5,6],[7,8,9]]
**Output:** [[1,4,7],[2,5,8],[3,6,9]]

Example 2:

**Input:** matrix = [[1,2,3],[4,5,6]]
**Output:** [[1,4],[2,5],[3,6]]

Constraints:

• m == matrix.length

• n == matrix[i].length

• 1 <= m, n <= 1000

• 1 <= m * n <= 105

• -109 <= matrix[i][j] <= 109

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