NW | 26-SDC-Mar | TzeMing Ho | Sprint 2 | improve with caches#171
NW | 26-SDC-Mar | TzeMing Ho | Sprint 2 | improve with caches#171TzeMingHo wants to merge 4 commits into
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TzeMingHo
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📅 Sprint 2
| def fibonacci(n, cache=None): | ||
| if cache == None: | ||
| cache={0:0, 1:1} | ||
| if n in cache: | ||
| return cache[n] | ||
| else: | ||
| value = fibonacci(n - 1, cache) + fibonacci(n - 2, cache) | ||
| cache[n] = value | ||
| return value |
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Could you research different approaches to make the cache reusable across multiple function calls (instead of repopulating it from the beginning)? Ideally, the approach does not involve using any global variable.
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I tried to use attributes. Is it a better way?
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Your implementation looks good.
Note: there is a much faster way to figure out how many ways we could make change when there is only 1 coin left to consider.
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So, when coin_index hits 7, which leads to coin value 1, we can simply return 1, right? No matter what the total is left, with coin value 1, it always gets 1 way.
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Correct.
I see that you have also figured out how to compute number of ways to make change when there is one coin left using %. Nice!
cjyuan
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TzeMingHo
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Changes look great. Well done. |
cjyuan
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In the making_change exercise, I have to discard the for loop and the while loop because it was difficult for me to understand what was happening. By implementing the take or leave the coin logic with coin_index, it explores the combinations with different starting coins. When total hits 0, it finds a way.