Given an m x n integers matrix, return the length of the longest increasing path in matrix.
From each cell, you can either move in four directions: left, right, up, or down. You may not move diagonally or move outside the boundary (i.e., wrap-around is not allowed).
m == matrix.lengthn == matrix[i].length1 <= m, n <= 2000 <= matrix[i][j] <= 2^31 - 1matrix = [[9,9,4],[6,6,8],[2,1,1]]4matrix = [[3,4,5],[3,2,6],[2,2,1]]4matrix = [[1]]1