(a) Outline, using a flow-chart or pseudo-code, the DavisPutnam (DP) algorithm for solving the problem of Boolean satisfiability (SAT). State how the processing time of the DP algorithm is related to the problem size in the worst case. Briefly outline possible modifications of DP that may lead to better computational performance. [15 marks] (b) Use the DP algorithm to find a combination of the variables $a, b, C, d$ which satisfy the following function: $$ f(a, b, c, d)=(\bar{a}+b+\bar{d})(a+\bar{b}+\bar{c})(\bar{c}+d). $$ cs. vs. 12421