Q. Write down the algorithm for binary search. Which are the conditions under which sequential search of a list is preferred over the binary search?                                                                   

Ans.

Algorithm for the Binary Search is as follows

1.  if (low> high)

2.  return (-1)

3.  Mid = (low + high)/2

4.  if ( X = = a[mid])

5.  return (mid);

6.  if (X < a[mid])

7.  search for X in a[low] to a[mid-1]

8.  else

9.  search for X in a[mid+1] to a[high]

Sequential Search is preferred over the binary search when the list is disorder and haphazardly constructed. When searching is to be done on unsorted list then linear search is the only option.