The code segment below prints some of the elements in an array with size n.Select an expression to complete the code segment so that the resulting algorithm has O(log n) running time.
A)(int j = 0; j

Question

The code segment below prints some of the elements in an array with size n.Select an expression to complete the code segment so that the resulting algorithm has O(log n) running time.  
A)(int j = 0; j < array.length; j = j + 2) 
B)(int j = 0; j < array.length / 2; j++) 
C)(int j = 1; j < array.length; j = j * 2) 
D)(int j = 0; j < array.length; j++)

Quizplus · Accepted Answer

Choice C uses a logarithmic scale for incrementing the loop counter. This is because at every iteration, the index j is multiplied by 2, so the maximum number of iterations is log2(n).
Choices A, B, and D all have linear time complexity, as they increment the loop counter by a constant amount per iteration or loop over all elements of the array.

The Code Segment Below Prints Some of the Elements in an Array