Mealy finite state machine that recognizes the word 10010. Over the arrows are the input, that causes the transition, and the output, that is the result of the transition, denoted as “input, output”. If the output is 1 then the FSM has recognized the sequence 10010. Also, the states of the FSM are drawn blue with the corresponding name inside of them.
\documentclass{standalone}
\usepackage{tikz}
\usetikzlibrary{automata, positioning, arrows, calc}
\tikzset{
->, % makes the edges directed
>=stealth, % makes the arrow heads bold
shorten >=2pt, shorten <=2pt, % shorten the arrow
node distance=3cm, % specifies the minimum distance between two nodes. Change if n
every state/.style={draw=blue!55,very thick,fill=blue!20}, % sets the properties for each ’state’ n
initial text=$ $, % sets the text that appears on the start arrow
}
\begin{document}
\begin{tikzpicture}
\node[state, initial] (s0) {$S_0$};
\node[state, right of=s0] (s1) {$S_1$};
\node[state, right of=s1] (s2) {$S_2$};
\node[state, right of=s2] (s3) {$S_3$};
\node[state, right of=s3] (s4) {$S_4$};
\draw (s0) edge[loop above] node{$0,0$} (s0)
(s0) edge[bend left] node[above]{$1,0$} (s1)
%
(s1) edge[bend left] node[above]{$0,0$} (s2)
(s1) edge[bend left] node[above]{$1,0$} (s0)
%
(s2) edge[bend left] node[above]{$0,0$} (s3)
(s2) edge[bend left=40] node[above]{$1,0$} (s0)
%
(s3) edge[bend left=50] node[above]{$0,0$} (s0)
(s3) edge[bend left] node[above]{$1,0$} (s4)
%
(s4) edge[bend right=50] node[above]{$0,1$} (s0)
(s4) edge[bend left=60] node[above]{$1,0$} (s0)
;
\end{tikzpicture}
\end{document}