Consider the following C code segment:

a = b + c;

e = a + 1;

d = b + c;

f = d + 1;

g = e + f;

In a compiler, this code segment is represented internally as a directed acyclic graph (DAG). The number of nodes of nodes in the DAG is ______

A lexical analyzer uses the following patterns to recognize three tokens $${T_1},{T_2},$$ and $${T_3}$$ over the alphabet $$\left\{ {a,b,c} \right\}.$$

$$\eqalign{ & {T_1}:\,\,\,a?{\left( {b|c} \right)^ * }a \cr & {T_2}:\,\,\,b?{\left( {a|c} \right)^ * }b \cr & {T_3}:\,\,\,c?{\left( {b|a} \right)^ * }c \cr} $$

Note that $$'x?'$$ means $$0$$ or $$1$$ occurrence of the symbol $$x.$$ Note also that the analyzer outputs the token that matches the longest possible prefix.

If the string $$bbaacabc$$ is processed by the analyzer, which one of the following is the sequence of tokens it outputs?

Which one of the following statements is FALSE?

Which one of the following grammars is free from $$left$$ $$recursion$$?