I_love_HellHoleStudios's blog

Introduction to an interesting set trick
By I_love_HellHoleStudios, history, 4 years ago, In English

I don't know if this trick was introduced or named earlier. But I found it interesting and decided to write a blog about it. The trick is simple and I wrote the blog simple too. Hope you don't get confused.

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Please ignore the Chinese interface.

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4 years ago, # |
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Using set seems overcomplicated because you can solve the problem mentioned in the blog without set at all just keeping current minimum and delta.

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    4 years ago, # ^ |
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    +1.

    The author should probably specify that a set could be used if adding a 4th operation like "check membership" (i.e. checking for $$$x$$$ corrresponds to searching the set for $$$x-\delta$$$)

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      4 years ago, # ^ |
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      Yes, that would have sense with such operation.

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4 years ago, # |
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This trick indeed has a name, it's offset. It allows adding something to all elements of a set.

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4 years ago, # |
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I dont understand how to execute operation 1, how is the delta added to all of the elements in the set?

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    4 years ago, # ^ |
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    [1, 2, 3] + 2 = [3, 4, 5]

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4 years ago, # |
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Venice Technique

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4 years ago, # |
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Might be irrelevant but, Here's the same question but with Xor as an operation: For the Curious Ones!

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4 years ago, # |
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Wow, the trick is amazing trick. Something new for me to learn today.

This trick using set will be more useful when there is one more query to be performed: delete element X. Just remove element (X − δ) from the set or treemap (in Java), and there you go.

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