Multiple of 3

Given a positive integer $N$, find the nearest multiple of $3$. Multiples of $3$ are $\ldots -6, -3, 0, 3, 6, 9, 12, 15, \ldots$. Formally, find $X$, the multiple of $3$ with minimum value of $|N - X|$. It can be proven that the answer is always unique, i.e. $2$ different multiples of $3$ cannot be nearest at the same time. ### Input - The only line of input contains a single integer $N$. ##