title: how do you test a calculator?
body: <p>How will you test a calculator? Any thoughts?</p>
  
  <p>thanks,</p>
  
  <p>===
  Sorry that I did not elaborate this question much at the beginning. Now, I want to give more backgrounds about this. This question was asked during a <strong>technical interview</strong> for a <strong>programmer</strong> position. So I suppose they were looking for some really "smart" answers or some good approach to test such application...</p>
  
  <p>Thanks again.</p>