GitHub Repository Submission

When using GitHub mode, paste your repository URL below and click Save URL to store it. The saved URL will be automatically included with every message you send until you choose to clear it. Learn more

Your GitHub repository URL is saved. LSBot will automatically fetch your latest code from this repository for each message. To change the URL, clear it first and save a new one.

Exercise 7

What is the time complexity of the function test? What is its space complexity?

function test(n) {
  let result = [];
  for (let i = 0; i < n; i++) {
    result.push(new Array(n).fill(0));
  }
  return result;
}

Solution

The time complexity is O(N^2) due to the creation of n arrays, each of size n.

The space complexity is also O(N^2) as the result array grows quadratically with the input size, holding n arrays of size n.

Let's explore the time complexity in detail:

  • The loop iterates n times, where n is the input size.
  • In each iteration of the loop, a new array of size n is created and filled with zeros. The new Array(n).fill(0) operation itself consists of two parts:
    • The creation of the array itself is typically considered an O(1) operation since it essentially allocates memory for n elements but doesn't initialize them.
    • The .fill(0) method operates linearly with respect to the size of the array it's filling. This part of the operation is O(n) because it involves setting each of the n elements in the newly created array to 0.

In summary, for each iteration of the loop, an array is created (O(1)) and then filled (O(n)). The dominant operation here is the filling of the array, which is O(n). Since this operation is repeated n times, the total time complexity is O(N^2).

Now the space complexity:

  • The result variable is an array that grows as new arrays are pushed into it.
  • Each of the n iterations of the loop adds a new array of size n to the result array.
  • By the end of the loop, the result array holds n arrays, each containing n elements. Therefore, the total space used is proportional to n * n elements. Thus, the space complexity is O(N^2), as the space required grows quadratically with the input size n.

Hi! I'm LSBot. I can help you think through the selected exercise by giving you hints and guidance without revealing the solution. Your code from the editor will be automatically detected. Want to know more? Refer to the LSBot User Guide .

Detected solution
Loading...

Submit your solution for LSBot review.

 Hi! I'm LSBot. Your code from the editor will be automatically detected. I'll review your solution and provide feedback to help you improve. Ask questions about your solution or request a comprehensive code review. Want to know more? Refer to the LSBot User Guide .

Detected solution
Loading...