91Ó°ÊÓ

In theory of computation, context free grammar (CFG) generates the possible strings in a language. CFG is in Chomsky normal form (CNF) if the production rules in it are of the following forms:

$$\begin{gathered} A→BC \\ A→a \end{gathered}$$

$$\begin{gathered} S→A \\ A→BAB\left|B\right|\mathrm{Î\mu } \\ B→00|\mathrm{Î\mu } \end{gathered}$$

The two ε-productions are:

$$\begin{gathered} A→\mathrm{Î\mu } \\ B→\mathrm{Î\mu } \\ Remove,A→\mathrm{Î\mu } \\ S→A|\mathrm{Î\mu } \\ A→BAB|BB⊙00|\mathrm{Î\mu } \\ RemoveB→\mathrm{Î\mu } \\ S→A|\mathrm{Î\mu } \\ A→BAB\left|AB\right|BA\left|BB\right|B|\mathrm{Î\mu } \\ B→00 \\ A→\mathrm{Î\mu }iscreatedagain. \\ RemoveA→\mathrm{Î\mu } \\ A→BAB|BB\left|AB\right|B\left|BA\right|\mathrm{Î\mu } \\ B→00 \\ RemoveA→\mathrm{Î\mu }again. \\ S→A|\mathrm{Î\mu } \\ A→BAB|BB\left|AB\right|B|BA \\ B→00 \end{gathered}$$

The two-unit productions are:

$$\begin{gathered} S→A \\ RemoveS→A. \\ S→BAB\left|BB\right|AB\left|B\right|BA|\mathrm{Î\mu } \\ A→BAB|BB\left|AB\right|B|BA \\ B→00 \\ RemoveS→B. \\ S→BAB|BB→\left|AB\right|00\left|BA\right|\mathrm{Î\mu } \\ A→BAB\left|BB\right|AB\left|B\right|BA3 \\ B→00 \\ RemoveA→B \\ S→BAB\left|BB\right|AB\left|00\right|BA|\mathrm{Î\mu } \\ A→BAB|BB\left|AB\right|00|BA \\ B→00 \end{gathered}$$

$$\begin{gathered} S→BD\left|BB\right|AB\left|CC\right|BA|\mathrm{Î\mu } \\ A→BD|BB\left|AB\right|CC|BA \\ B→CC \\ C→0 \\ D→AB \end{gathered}$$