title: Regex create a expression solving the following pattern
body: <p>This is part of a university optional homework and we are kinda struggling a bit.</p>
  
  <p>The pattern to solve isn't that hard to be honest we don't get our heads around it,  create a expression that has the alphabet {a,b,c} contains at least one <code>a</code> and one <code>b</code>. </p>
  
  <p>current two approaches are </p>
  
  <p><code>(a|b|c)*a(a|b|c)*b(a|b|c)* or (a|b|c)(a|b)(a|b|c)*(a|b)(a|b|c)*</code></p>
  
  <p>But both of these have flaws first one wouldnt allow ccbacc second one would allow ccaacc.</p>
  
  <p>Greetings </p>