Linear operators and matrices

Consider the operator $\mathcal{S}$ in $\mathbb{R}^3$ that shifts all coordinates of a vector to the right and puts the third coordinate in place of the first coordinate. Here's what it does to the vector $a \in \mathbb{R}^3$ with coordinates $(a_1, a_2, a_3)$:

$$\mathcal{S}\begin{pmatrix} a_1\\a_2\\a_3 \end{pmatrix}= \begin{pmatrix} a_3\\a_1\\a_2 \end{pmatrix}$$Find the matrix of the operator $\mathcal{S}$ in the standard basis: $e_1 = (1, 0, 0)$, $e_2 = (0, 1, 0)$, $e_3 = (0, 0, 1)$. Write it in the answer field. Your answer may look as follows:

0 0 0
0 0 0
0 0 0