yshen94's blog

performance difference bewteen array and vector
By yshen94, 8 hours ago, In English

really curious about the performance difference bewteen array and vector.

for 2023A — Concatenation of Arrays,

I passed the test using array as in #287237470 while failed the test using vector as in #287234748. The error shows "exit code: -1073741819 (STATUS_ACCESS_VIOLATION), checker exit code: 0, verdict: RUNTIME_ERROR"

maybe I am quite new in Codeforces. will be digging deeper into the performance difference.

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7 hours ago, # |
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Your cmp function is broken. The comparator should return false on elements that you consider equivalent: it should be return x.x+x.y < y.x+y.y;.

That is probably part of the reason for the runtime error, not some minute performance difference.

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    7 hours ago, # ^ |
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    You are right, appreciate your explanation. but why cannot I have an equivalent sign?

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      4 hours ago, # ^ |
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      C++ comparator should define the < sign. Using this, we automatically get the other two cases: x > y = !(x < y) and x == y = !(x < y) && !(x > y)

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7 hours ago, # |
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I made the same mistake that my comparator returns true if elements are equivalent. After receiving a runtime error I passed the code for ChatGPT for debugging. It immediately pinpointed the bug.. Most of the time, AI tools help me debug really quickly.

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    6 hours ago, # ^ |
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    why were the first 3 testcases passed successfully?

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      4 hours ago, # ^ |
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      Might be because equality comparison in never used in these tc

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