Count Unique Paths

Given a grid of size m x n, where m is the number of rows and n is the number of columns, determine the number of unique paths from the top-left corner to the bottom-right corner. You can only move right or down at any point in time. Implement the function requiring recursion. Example: For a 2x2 grid, the output should be 2, as there are two paths: right->down and down->right.