Challenge: Binary Search

Complete the doSearch function so that it implements a binary search, following the pseudo-code below (this pseudo-code was described in the previous article):

1. Let min = 0 and max = n - 1.
   

2. If max < min, then stop: target is not present in array. Return -1.
   

3. Compute guess as the average of max and min, rounded down (so that it is an integer).
   

4. If array[guess] equals target, then stop. You found it! Return guess.
   

5. If the guess was too low, that is, array[guess] < target, then set min = guess + 1.
   

6. Otherwise, the guess was too high. Set max = guess - 1.
   

7. Go back to step 2.