\newpage \subsection{Connected Components} \begin{definition}[]{Connected Component} A \textbf{connected component} of a graph $G = (V, E)$ is a maximal subset of vertices $C \subseteq V$ such that: \begin{itemize} \item For every pair of vertices $u, v \in C$, there exists a path connecting $u$ and $v$. \item Adding any vertex $w \notin C$ to $C$ would violate the connectedness condition. \end{itemize} \end{definition} \begin{remarks}[]{Key Points About Connected Components} \begin{itemize} \item \textbf{Undirected Graphs:} A connected component is a subgraph where any two vertices are connected by a path, and which is connected to no additional vertices in the graph. \item \textbf{Directed Graphs:} There are two types of connected components: \begin{itemize} \item \textbf{Strongly Connected Component:} A maximal subset of vertices where every vertex is reachable from every other vertex (considering edge direction). \item \textbf{Weakly Connected Component:} A maximal subset of vertices where connectivity is considered by ignoring edge directions. \end{itemize} \end{itemize} \end{remarks} \begin{example}[]{Connected Components in a Graph} \begin{center} \begin{tikzpicture}[node distance=1.5cm, main/.style={circle, draw, fill=blue!20, minimum size=10mm, inner sep=0pt}] % Connected component 1 \node[main] (1) {1}; \node[main] (2) [right of=1] {2}; \node[main] (3) [below of=1] {3}; \draw (1) -- (2); \draw (1) -- (3); \draw (2) -- (3); % Connected component 2 \node[main] (4) [right of=2, xshift=2cm] {4}; \node[main] (5) [right of=4] {5}; \draw (4) -- (5); % Isolated vertex (another component) \node[main] (6) [below of=5, yshift=-1cm] {6}; \end{tikzpicture} \end{center} \end{example} \begin{remarks}[]{Understanding the Example} \begin{itemize} \item In the given undirected graph: \begin{itemize} \item \textbf{Component 1:} $\{1, 2, 3\}$ (fully connected subgraph). \item \textbf{Component 2:} $\{4, 5\}$ (connected by a single edge). \item \textbf{Component 3:} $\{6\}$ (an isolated vertex). \end{itemize} \item These subsets are disjoint and collectively partition the graph's vertex set $V$. \end{itemize} \end{remarks}