\hspace{-0.09cm}\scalebox{0.85}{ \begin{dplltabular}{4} \dpllStep{1|2|3|4} \dpllDecL{0|1|1|1} \dpllAssi{ - |$a$|$a, \lnot c$|$a, \lnot c, b$} \dpllClause{1}{$a, b$}{$a, b$|\done|\done|\done} \dpllClause{2}{$\lnot b, c$}{$\lnot b, c$|$\lnot b, c$|$\lnot b$|\conflict} \dpllClause{3}{$\lnot a, \lnot c$}{$\lnot a, \lnot c$|$\lnot c$|\done|\done} \dpllClause{4}{$b, c$}{$b, c$|$b, c$|$b$|\done} \dpllClause{5}{$a, \lnot b$}{$a, \lnot b$|\done|\done|\done} \dpllBCP{ - |$\lnot c$|$b$| - } \dpllPL{ - | - | - | - } \dpllDeci{$a$| - | - | - } \end{dplltabular} } Conflict in step 4\\ \scalebox{0.75}{ \begin{tikzpicture}[>=latex,line join=bevel,] \pgfsetlinewidth{1bp} %% \pgfsetcolor{black} % Edge: 1 -> 4 \draw [->] (22.3bp,31.0bp) .. controls (35.47bp,31.0bp) and (58.583bp,31.0bp) .. (85.878bp,31.0bp); \definecolor{strokecol}{rgb}{0.0,0.0,0.0}; \pgfsetstrokecolor{strokecol} \draw (54.0bp,38.5bp) node {$$3$$}; % Edge: 3 -> 2 \draw [->] (193.67bp,47.438bp) .. controls (201.41bp,44.585bp) and (212.51bp,40.495bp) .. (231.47bp,33.51bp); % Edge: 4 -> 3 \draw [->] (107.97bp,33.373bp) .. controls (121.23bp,36.53bp) and (144.98bp,42.186bp) .. (172.05bp,48.63bp); \draw (140.0bp,50.5bp) node {$$2$$}; % Edge: 4 -> 5 \draw [->] (107.11bp,26.371bp) .. controls (112.48bp,23.828bp) and (119.48bp,20.828bp) .. (126.0bp,19.0bp) .. controls (137.65bp,15.733bp) and (151.06bp,13.758bp) .. (171.92bp,11.639bp); \draw (140.0bp,26.5bp) node {$$4$$}; % Edge: 5 -> 2 \draw [->] (193.67bp,14.223bp) .. controls (201.24bp,16.746bp) and (212.02bp,20.339bp) .. (231.09bp,26.697bp); % Node: 1 \begin{scope} \definecolor{strokecol}{rgb}{0.0,0.0,0.0}; \pgfsetstrokecolor{strokecol} \draw (11.0bp,31.0bp) ellipse (11.0bp and 11.0bp); \draw (11.0bp,31.0bp) node {$a$}; \end{scope} % Node: 4 \begin{scope} \definecolor{strokecol}{rgb}{0.0,0.0,0.0}; \pgfsetstrokecolor{strokecol} \draw (97.0bp,31.0bp) ellipse (11.0bp and 11.0bp); \draw (97.0bp,31.0bp) node {$\lnot c$}; \end{scope} % Node: 2 \begin{scope} \definecolor{strokecol}{rgb}{0.0,0.0,0.0}; \pgfsetstrokecolor{strokecol} \draw (242.0bp,30.0bp) ellipse (11.0bp and 11.0bp); \draw (242.0bp,30.0bp) node {$\bot$}; \end{scope} % Node: 3 \begin{scope} \definecolor{strokecol}{rgb}{0.0,0.0,0.0}; \pgfsetstrokecolor{strokecol} \draw (183.0bp,51.0bp) ellipse (11.0bp and 11.0bp); \draw (183.0bp,51.0bp) node {$\lnot b$}; \end{scope} % Node: 5 \begin{scope} \definecolor{strokecol}{rgb}{0.0,0.0,0.0}; \pgfsetstrokecolor{strokecol} \draw (183.0bp,11.0bp) ellipse (11.0bp and 11.0bp); \draw (183.0bp,11.0bp) node {$b$}; \end{scope} % \end{tikzpicture} } \begin{prooftree} \AxiomC{$2. \; \lnot b \lor c$} \AxiomC{$4. \; b \lor c$} \BinaryInfC{$c$} \AxiomC{$3. \; \lnot a \lor \lnot c$} \BinaryInfC{$\lnot a$} \end{prooftree} \hspace{-0.09cm}\scalebox{0.85}{ \begin{dplltabular}{3} \dpllStep{5|6|7} \dpllDecL{0|0|0} \dpllAssi{ - |$\lnot a$|$\lnot a, b$} \dpllClause{1}{$a, b$}{$a, b$|$b$|\done} \dpllClause{2}{$\lnot b, c$}{$\lnot b, c$|$\lnot b, c$|$c$} \dpllClause{3}{$\lnot a, \lnot c$}{$\lnot a, \lnot c$|\done|\done} \dpllClause{4}{$b, c$}{$b, c$|$b, c$|\done} \dpllClause{5}{$a, \lnot b$}{$a, \lnot b$|$\lnot b$|\conflict} \dpllClause{6}{$\lnot a$}{$\lnot a$|\done|\done} \dpllBCP{$\lnot a$|$b$| - } \dpllPL{ - | - | - } \dpllDeci{ - | - |UNSAT} \end{dplltabular} } Conflict in step 7\\ \scalebox{0.75}{ \begin{tikzpicture}[>=latex,line join=bevel,] \pgfsetlinewidth{1bp} %% \pgfsetcolor{black} % Edge: 0 -> 4 \draw [->] (1.0536bp,31.0bp) .. controls (2.5071bp,31.0bp) and (33.188bp,31.0bp) .. (64.696bp,31.0bp); \definecolor{strokecol}{rgb}{0.0,0.0,0.0}; \pgfsetstrokecolor{strokecol} \draw (33.0bp,38.5bp) node {$$6$$}; % Edge: 2 -> 1 \draw [->] (172.67bp,47.438bp) .. controls (180.41bp,44.585bp) and (191.51bp,40.495bp) .. (210.47bp,33.51bp); % Edge: 3 -> 1 \draw [->] (172.67bp,14.223bp) .. controls (180.24bp,16.746bp) and (191.02bp,20.339bp) .. (210.09bp,26.697bp); % Edge: 4 -> 2 \draw [->] (86.966bp,33.373bp) .. controls (100.23bp,36.53bp) and (123.98bp,42.186bp) .. (151.05bp,48.63bp); \draw (119.0bp,50.5bp) node {$$1$$}; % Edge: 4 -> 3 \draw [->] (86.111bp,26.371bp) .. controls (91.482bp,23.828bp) and (98.482bp,20.828bp) .. (105.0bp,19.0bp) .. controls (116.65bp,15.733bp) and (130.06bp,13.758bp) .. (150.92bp,11.639bp); \draw (119.0bp,26.5bp) node {$$5$$}; % Node: 4 \begin{scope} \definecolor{strokecol}{rgb}{0.0,0.0,0.0}; \pgfsetstrokecolor{strokecol} \draw (76.0bp,31.0bp) ellipse (11.0bp and 11.0bp); \draw (76.0bp,31.0bp) node {$\lnot a$}; \end{scope} % Node: 1 \begin{scope} \definecolor{strokecol}{rgb}{0.0,0.0,0.0}; \pgfsetstrokecolor{strokecol} \draw (221.0bp,30.0bp) ellipse (11.0bp and 11.0bp); \draw (221.0bp,30.0bp) node {$\bot$}; \end{scope} % Node: 2 \begin{scope} \definecolor{strokecol}{rgb}{0.0,0.0,0.0}; \pgfsetstrokecolor{strokecol} \draw (162.0bp,51.0bp) ellipse (11.0bp and 11.0bp); \draw (162.0bp,51.0bp) node {$b$}; \end{scope} % Node: 3 \begin{scope} \definecolor{strokecol}{rgb}{0.0,0.0,0.0}; \pgfsetstrokecolor{strokecol} \draw (162.0bp,11.0bp) ellipse (11.0bp and 11.0bp); \draw (162.0bp,11.0bp) node {$\lnot b$}; \end{scope} % \end{tikzpicture} } \begin{prooftree} \AxiomC{$1. \; a \lor b$} \AxiomC{$5. \; a \lor \lnot b$} \BinaryInfC{$a$} \AxiomC{$6. \; \lnot a$} \BinaryInfC{$\bot$} \end{prooftree}