The set of connected components for $G$ is the D180: Quotient set
\begin{equation}
X / { \leftrightarrow }
= \{ \leftrightarrow(x) : x \in X \}
\end{equation}
The set of connected components for $G$ is the D180: Quotient set
\begin{equation}
X / { \leftrightarrow }
= \left\{ \{ y : (x, y) \in {\leftrightarrow} \} : x \in X \right\}
\end{equation}