Rotate Square Matrix In Place

Problem

Given an n x n matrix of integers represented as a list of lists, rotate the matrix 90 degrees clockwise in place. Modify the input matrix directly and return it. You may not allocate another n x n matrix for the result.

Constraints

• 1 <= n <= 20
• matrix.length == n
• matrix[i].length == n
• -1000 <= matrix[i][j] <= 1000