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 ### Handwork
 
 * Thompson's construction (RE -> NFA)
-* Subset Construction(NFA -> DFA)
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+* Subset Construction(NFA -> DFA)
+
+
+DFA Optimization
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+# 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
+
+
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