move *.md to notes/*.md and add lecture pdf

notes/2.md

@@ -118,3 +118,6 @@ main() {
 
 * Thompson's construction (RE -> NFA)
 * Subset Construction(NFA -> DFA)
+
+
+DFA Optimization

notes/3.md

@@ -0,0 +1,23 @@
+# Syntax Analysis
+
+
+## Context-Free Grammars (CFG)
+
+## Parse Tree
+
+A tree representation of the derivation
+
+parse tree has `terminals` at the leaves, `non-terminals` at the interior.
+
+An in-order traversal of the leaves is the original input.
+
+* leftmost derivation
+* rightmost derivation
+
+### Ambiguity
+
+should be resolved
+
+for example: `A + B * C` should be resolved
+
+