Bash Matrix

A Bash matrix is a matrix with $N$ rows (numbered $1$ through $N$) and $N$ columns (numbered $1$ through $N$), where for each row $r$ and column $c$, the cell in row $r$ and column $c$ (denoted by $(r, c)$) contains one of the characters 'U', 'D', 'L' or 'R'. We can move in the matrix while treating the characters as instructions: - If the character in the cell $(r,c)$ is 'R', move to the righ