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Tonmoy has a special torch. The torch has $4$ **levels** numbered $1$ to $4$ and $2$ **states** ($\texttt{On}$ and $\texttt{Off}$). Levels $1, 2,$ and $3$ correspond to the $\texttt{On}$ state while level $4$ corresponds to the $\texttt{Off}$ state. The **levels** of the torch can be changed as: - Level $1$ changes to level $2$. - Level $2$ changes to level $3$. - Level $3$ changes to level $4$.