aneee's blog

Doubt Regarging std::unique() | AC vs WA
By aneee, history, 4 years ago, In English

Problem.

I solved the problem with three pointers. But when I sort the vectors first and the resize, I get an AC. If I sort them after making them unique, I get a WA.

AC Code
WA Code
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4 years ago, # |
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Unique requires the vector to be sorted. All it does is check if adjacent elements are equal.

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4 years ago, # |
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unique only causes consecutive groups of identical elements to be condensed. So you need to sort first.

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    4 years ago, # ^ |
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    Thank you! So I guess there is no way to extract unique elements, maintaining the given order?

    ^ using an std algorithm I mean.

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      4 years ago, # ^ |
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      In a way, you can. For instance if you do unique on the array

      5 5 5 0 0 1 0 0 2 2 5 5 5 5 5

      you would get

      5 0 1 0 2 5.
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