A Common-Sense Guide to Data Structures and Algorithms, Second Edition, 2nd Edition

Exercises

The following exercises provide you with the opportunity to practice analyzing algorithms. The solutions to these exercises are found in the section, ​Chapter 5​.

1. Use Big O Notation to describe the time complexity of an algorithm that takes 4N + 16 steps.

2. Use Big O Notation to describe the time complexity of an algorithm that takes 2N².

3. Use Big O Notation to describe the time complexity of the following function, which returns the sum of all numbers of an array after the numbers have been doubled:

   def double_then_sum(array)
     doubled_array = []
   
     array.each do |number|
       doubled_array << number *= 2
     end
   
     sum = 0
   
     doubled_array.each do |number|
       sum += number
     end
   
     return sum
   end

4. Use Big O Notation ...