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0 pointsajuc1y ago0 comments

Let's say you have a lookup table and your algorithm looks up a value and returns it. O(n) space O(1) in time.

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n is some value depending on the size of the input, so if you have a look up table that is O(n), then that memory needs to be initialized somehow. If you have a fixed size lookup table then it is O(1), even if it is big.

ajucOP1y ago

Compile time fill a lookup table. Run time read 1 value from it. I call it O(1) in time, O(n) in memory. You call it O(1) in both, right?

Now move the compile time code to runtime.

I call it O(n) in time and memory. What do you call it?

If your say O(n) in time and memory - why is moving the code changing its complexity?

If you say still O(1) - then everything is O(1), thus proving P=NP among other things :)

Either way your interpretation isn't very useful.

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