\begin{tikzpicture}

%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%
%% My Customized Styles
%%

[node distance=2cm]% automatically spaced 2cm apart from their centres

%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%
%% My Customized Components
%%

\tikzstyle{startstop} = [% use for start and stop blocks
    rectangle,
    rounded corners=0.5cm,
    minimum width=3cm,
    minimum height=1cm,
    text centered,
    text width=3cm,
    text badly centered,
    draw=black,
    fill=red!30
]
\tikzstyle{data} = [% style for data
    trapezium,
    trapezium left angle=66,
    trapezium right angle=-66,
    minimum width=0,
    minimum height=1cm,
    inner sep=0pt,
    outer sep=0pt,
    text centered,
%   text width=1.5cm,
    text badly centered,
    draw=black,
    fill=white
]
\tikzstyle{print} = [% style for print
    tape,
    tape bend top=none,
    minimum width=3cm,
    minimum height=1cm,
    inner sep=0pt,
    outer sep=0pt,
    text centered,
%   text width=1.5cm,
    text badly centered,
    draw=black,
    fill=white
]
\tikzstyle{io} = [% specify an input or output box
    trapezium,
    trapezium left angle=66,
    trapezium right angle=-66,
    minimum width=3cm,
    minimum height=1cm,
    text centered,
    text width=1.5cm,
    text badly centered,
    draw=black,
    fill=blue!30
]
\tikzstyle{loopevent} = [% style for loop or event blocks
    chamfered rectangle,
    minimum width=3cm,
    minimum height=1cm,
    text centered,
    text width=1.5cm,
    text badly centered,
    draw=black,
    fill=yellow!30
]
\tikzstyle{process instruction} = [% style for process blocks
    rectangle,
    minimum width=3cm,
    minimum height=1cm,
    text centered,
    text width=3cm,
    text badly centered,
    draw=black,
    fill=orange!30
]
\tikzstyle{process function} = [% style for pre-defined process blocks
    rectangle split,
    rectangle split horizontal,
    rectangle split parts = 3,
    rectangle split empty part width=-8pt,
    minimum width=3cm,
    minimum height=1cm,
    text centered,
%   text width=3cm,
    text badly centered,
    draw=black,
    fill=orange!30
]
\tikzstyle{decision} = [% style for decision blocks
    diamond,
    minimum width=3cm,
    minimum height=1cm,
    text centered,
    text width=1.5cm,
    text badly centered,
    draw=black,
    fill=green!30
]
\tikzstyle{arrow} = [% style for the arrows
    thick,->,>=stealth
]

%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%
%% Flowchart
%%

% our start block
\node (start) [startstop] {Start};

% add an input block in below the start block
\node (in1) [io,below of=start,yshift=-0.5cm] {Input};

% add in a process block and a decision block
\node (ins1) [process instruction,below of=in1] {Instruction 1};
% yshift should make the gap more regular
\node (dec1) [decision,below of=ins1,yshift=-0.5cm] {Decision};

% add in two process blocks coming out of the decision block
\node (ins2a) [process instruction,below of=dec1,yshift=-1.5cm] {
    Instruction 2a:
    This is a process with a very long description text within a single paragraph.
};
\node (fun2b) [process function,right of=dec1,xshift=2cm] {
    \nodepart[text width=2.5cm]{two}{Function 2b}
};

% finish off adding the blocks by adding in an output block and a stop block
\node (out1) [io,below of=ins2a,yshift=-1cm] {Output};
\node (stop) [startstop,below of=out1,yshift=-0.5cm] {Stop};

% arrows
\draw [arrow] (start) -- (in1);
\draw [arrow] (in1) -- (ins1);
\draw [arrow] (ins1) -- (dec1);
% arrows coming out of a decision block need some text (node) with anchor
\draw [arrow] (dec1) -- node[anchor=east] {yes} (ins2a);
\draw [arrow] (dec1) -- node[anchor=south] {no} (fun2b);
% final arrows
\draw [arrow] (fun2b) |- (ins1); % swap the first dash for a bar symbol which
                                 % will make the arrow go in a vertical
                                 % direction before going in a horizontal
                                 % direction
\draw [arrow] (ins2a) -- (out1);
\draw [arrow] (out1) -- (stop);

% add in a event block beside with a data block
\node (ev1) [loopevent,left of=in1,xshift=-2cm] {Event};
\node (dat1) [data,above of=ev1,yshift=-0.5cm] {CON:};
\draw [arrow] (dat1) -- (ev1);
\draw [arrow,dashed] (ev1) -- (in1);

% add in a loop block beside with a print block
\node (lp1) [loopevent,right of=out1,xshift=2cm] {Loop};
\node (prn1) [print,below of=lp1,yshift=0.5cm] {PRN:};
\draw [arrow,dashed] (out1) -- (lp1);
\draw [arrow] (lp1) -- (prn1);

%%
%%
%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\end{tikzpicture}

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