uniquePaths = (row, col, memo = getMemo(row, col)) => {
    const isBaseCase = ((row === 1) || (col === 1));
    if (isBaseCase) return 1;

    const hasSeen = (memo[row][col] !== 0);
    if (hasSeen) return memo[row][col];

    return dfs(row, col, memo);/* Time O(ROWS * COLS) | Space O((ROWS * COLS) + HEIGHT) */
}
DP - Top Down
Matrix - Memoization
Time O(ROWS * COLS) | Space O(ROWS * COLS)
https://leetcode.com/problems/unique-paths/
@param {number} m
@param {number} n
@return {number}