NoTwo's blog

Need help with 446C
By NoTwo, history, 9 years ago, In English

Hello,
I'm trying to solve 446C - DZY Loves Fibonacci Numbers and i can't debug my code. I'm simply using a segment tree to get the sums.I would really be happy if someone could tell me my mistakes.

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9 years ago, # |
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I guess you misunderstood the problem, for each update you should do following from L to R: a[L] += f[L], a[L + 1] += f[L + 1] ... a[R] += f[R]

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    9 years ago, # ^ |
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    nope it says for each l <= i <= r: a[i] += f[i-l+1] thus a[l] += f[1], a[l+1] += f[2], ..., a[r] += f[r-l+1]

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      9 years ago, # ^ |
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      Ok, the wrong part is you add pf[q — p — 1] to all a[i] from l to r

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        9 years ago, # ^ |
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        i tried pf[q-p] before, still wrong :(

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          9 years ago, # ^ |
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          Yes, it must be wrong, you can not do updates correctly with this approach because every element doesn't get constant number and its correct solution isn't as simple as you think, try to look others code or tutorial to get the idea

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