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Is < 1500 pretty much just all finding patterns?
By BuiltDifferent, history, 2 years ago, In English

Hello,

I'm very new to this, and I've only done a couple contests so far. In my limited experience, the newbie questions I did were all based on patterns which you notice manually not computationally. Is this the case until any specific rating or just in general?

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2 years ago, # |
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As far as I know, many of the lower-rated questions are known as "Ad-Hoc". These are problems where there is no general technique to solve them and solving them is based on the specific details of the problem. I think this is what you are talking about. But I have also seen many binary search or dp problems that appear <1500, so definitely not all of them are like that(but then again I'm also not that experienced).

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    2 years ago, # ^ |
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    I appreciate the insight, thank you! I've heard that < 1300 is roughly comparable to USACO Bronze, so what would Silver/Gold/Platinum be comparable to?

    It's all good if you aren't sure, I'm just trying to gauge a level to replicate or achieve.

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      2 years ago, # ^ |
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      This is what USACO Guide says. Hope this helps.

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        2 years ago, # ^ |
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        That's insightful thank you!

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          2 years ago, # ^ |
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          USACO Gold is probably 1800-2500 range ngl. I got 0 points last gold contest as a candidate master (1900 rating).

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            2 years ago, # ^ |
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            Last USACO Gold was depressing. I think I fully solved two and didn't manage to get a partial score on one problem and the cutoff was 800 points like bruh

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2 years ago, # |
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I do not know what you mean by patterns, but I would say <= 1500 are often based on 'observations', which usually do not conform to any existing pattern. (well unless you break down the problem a bit then you can identify some patterns you may know but that's a byproduct of solving the problem)

These observations are at all rated ranges, become harder to grab on to, and tougher to accept because instead of being simple intuitive observations they start being somewhat non-intuitive and reliant on proofs.

I would say till 1900 one doesn't have to worry too much about proofs but more about making critical observations, although it is good practice to prove later during upsolving.

Feel free to correct me.

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2 years ago, # |
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I would say <=1200 is pattern observation.

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    2 years ago, # ^ |
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    I would say <=1100 is pattern observation.

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      2 years ago, # ^ |
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      Is there really a significant difference between 1100 and 1200?

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        2 years ago, # ^ |
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        1100 vs 1200

        1100: just brute force.
        1200: it needs binary search and prefix sum.

        It's just div 4 round and there is this gap between its problems.

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          2 years ago, # ^ |
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          That's fair, I guess it's a pretty blurry boundary.

          BTW, congrats on solving almost 3300 problems! You must be very motivated and knowledgeable!

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