Problem Statement  
You are developing a new calculator with a square root function. To make things simple for your clients, you have decided to approximate square roots as simple fractions, rather than displaying a long sequence of digits. You will be given N and D and should return the fraction closest to sqrt(N) for which the denominator is not greater than D. The fraction should be returned in the form "A/B" where A and B are positive integers with no common factors greater than one.  
Definition  
 
Constraints  
  N will be between 1 and 1000000, inclusive.  
  D will be between 1 and 1000, inclusive.  
Examples  
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