Change Row and Column Both

There is a $10 \times 10$ grid with rows numbered $1$ to $10$ from top to bottom, and columns $1$ to $10$ from left to right. Each cell is identified by a pair $(r, c)$ which means that the cell is located at row $r$ and column $c$. If Chef's current location is $(a,b)$, then in one move Chef can go to $(c,d)$ if **both** of the following are satisfied: - $a \neq c$ - $b \neq d$ If the starting