backBencher24's blog

Need help in figuring it out different behaviour of output of exact same code in different IDE's with same compiler version
By backBencher24, history, 4 years ago, In English

In contest Codeforces Round 670 (Div. 2) when I submitted my code 92619898 for 1406B - Maximum Product It showed me output for 1st test case as

Output
-120
-12
0
0

and when I tested the same code for the 1st test case on my compiler as well as other online IDE's (CodeChef) compiler with the same version, the output was

Output
-120
-12
0
945

I am much confused about this behaviour and tried a lot but still unable to figure it out, Please help me in this

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4 years ago, # |
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The problem can be overflow. While subtracting from something.size() it can overflow. I typecasted all those kind of subtraction to (int)something.size() — 1. Then it passed the first test. Click

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    4 years ago, # ^ |
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    thanks kenechi

    I tried that solution 92700187 submitting again (by removing mistakes) and It passed all pretest by typecasting that you told above

    but if I remove that it says runtime error 92700090 for 2nd test case, if there is any overflow, so how it is passing all the test cases for a solution 92700187 by doing typecasting only (it should be giving the wrong answer)

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      4 years ago, # ^ |
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      Try running this

      Code

      The size type variable doesn't support negative values so when you subtract something bigger from it, it prints arbitrarily large value.

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        4 years ago, # ^ |
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        okay, thanks :) I will be more careful to avoid these issues

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4 years ago, # |
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In that particular test case, the value of your l1 variable becomes -1, thus causing undefined behavior.

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