Regex Intersection Checker

• Literals: a, b, 0, etc.
• Concatenation: ab (a followed by b)
• Alternation: a|b (a or b)
• Kleene star: a* (zero or more a's)
• Plus: a+ (one or more a's)
• Optional: a? (zero or one a)
• Grouping: (ab)*

Example Pairs

• a*b and ab* → ab
• (ab)* and (ba)* → ε (empty string)
• a+ and a*b → ab
• (0|1)*0 and 0(0|1)* → 0