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CheezItMan
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Nov 14, 2019
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Well you didn't get too far but the methods you have work, although they have issues with time/space complexity. Take a look at my notes and let me know if you have questions.
| # Space complexity: ? | ||
| # Time complexity: O(n) | ||
| # Space complexity: O(n) | ||
| def factorial(n) |
| if s.length <= 1 | ||
| return s | ||
| else | ||
| return reverse(s[1..-1]) + s[0] |
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s[1..-1] creates a new array and copies all the individual elements over and so is O(n) by itself.
| # Space complexity: ? | ||
| # Time complexity: O(n) | ||
| # Space complexity: O(n) | ||
| def reverse(s) |
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👍
This works, but because you create a new array with each recursive call this is O(n2) for both time/space complexity.
| # Space complexity: ? | ||
| # Time complexity: O(n) | ||
| # Space complexity: O(n) | ||
| def is_palindrome(s) |
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👍 This works, but you have similar time/space issues with the above methods due to creating new arrays.
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Finished palindrome, reverse, factorial