Big O notation + log

Question 1

What is big O notation

Answer 1

Describes the time and space complexity of an alogorithm

Question 2

Explain what log2(n) means

Answer 2

This means the number of times you can divide n by before reaching 1

Question 3

Give an example of log2(n)

Answer 3

log2(8) = 8 - 4 - 2 - 1. This would be 3 visits

Question 4

what Big o notation is binary search

Answer 4

O(log n) - Binary search works by repeatedly dividing the search space in half:

Start with a sorted array.

Compare the target to the middle element.

If the target is smaller, discard the right half; if larger, discard the left half.

Repeat until the target is found or the search space is empty.

Since the array is halved each time, the number of steps grows logarithmically with input size (n)

Question 5

what equation is selection sort

Answer 5

n2 - quadratic time, ineficiant for large data sets. This is because it makes mutiple comparisons.

Question 6

What is black box testing

Answer 6

• Testing functionallility without knowing internal code
• Testing from a users perspective

Question 7

what is white box testing

Answer 7

• testing the soruce code and internal code structure
• The goal is to test every possible possibillity

Question 8

Give me a simple recursive method

Answer 8

int fact (int n){
if (n == 1){
return 1
}else{
n * fact(n - 1);
}
}

• loops keeps running until the base case it met