Consider the grammar with non-terminals N = { S, C, S₁ }, terminals T = { a, b, i, t, e }, with S as the start symbol, and the following set of rules:

$$\eqalign{ & S \to iCtS{S_1}\,|\,\,a \cr & {S_1} \to eS\,|\,\,\varepsilon \cr & C \to b \cr} $$

The grammar is NOT LL(1) because:

Consider the CFG with { S, A, B } as the non-terminal alphabet, { a, b } as the terminal alphabet, S as the start symbol and the following set of production rules:

$$\eqalign{ & S \to bA\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,S \to aB \cr & A \to a\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,B \to b \cr & A \to aS\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,B \to bS \cr & S \to bAA\,\,\,\,\,\,\,\,\,\,\,B \to aBB \cr} $$

For the correct answer strings to the previous question, how many derivation trees are there?

Consider the following grammar:

$$\eqalign{ & S \to FR \cr & R \to *S\,|\,\varepsilon \cr & F \to id \cr} $$

In the predictive parser table, M, of the grammar the entries $$M\left[ {S,id} \right]$$ and $$M\left[ {R,\$ } \right]$$ respectively.

In the correct grammar of the previous question, what is the length of the derivation (number of steps starring from S) to generate the string $${a^l}{b^m}$$ with $$l \ne m$$?