Don't use sqrt because precision issues

Also here is implementation to find floor(sqrt(x))

```
#define int long long
int sqrt(int x){
int l=1,r=1e9+5,ans=0,mid;
while (l<=r){
mid=(l+r)/2;
if (mid*mid<=x){
ans=mid;
l=mid+1;
}else r=mid-1;
}return ans;
}
```

It seems std::sqrt works fine in C++17 though. Also sqrtl seems to give correct results

I used sqrtl and AC B in my first try

I'm not sure about sqrtl, but I think it might have precision issues too. I think coding sqrt using binary search can be best because it's dealing with integers.

yeah binary search implementation is great

but usually sqrtl works. Sad for you u solved only A :((

It's ok, I'm used to heavy drops

Sad for you u use alt to reply :((

Sad for you u are expected to have -51 rating change as expected by carrot :((

Sad for you, your blogs talks about people breaking the contest rules, yet u break them and admitting it :((

Hmm. I guess your logic has some holes. What proves to you I use alt accounts in contests? Maybe, I used sqrtl and submitted on my main account during contest time and I just use this alt account for sharing some useful piece of info as I don't like writing from my main.

Could you provide an example ?

Based on what I've seen in your blogs, it appears to me that you engage in contribution farming

More holes in your logic. Wasn't sharing the helpfulness of sqrtl() in such problems for c++20 something useful? that it got +29 ups. Another past incidence, a colleague of yours Yousef_Sameh asked for help regarding map and unordered_map and I explained why the HashMap got TLE thru hacks, here

And isn't this your comment and this also . It looks to me you engage in contribution farming.

Aren't those mentioned comments contribution farming? Besides most of my contribution was got from catching cheaters who spoil the platform or thanking Mike for his efforts like this blog

However, PEACE out! I see this discussion of no relation to the post

Good luck for your CP journey.

Well, technically you are newbie.

sqrtl works fine for numbers up to $$$2^{62}$$$, which is imo enough for most cases. source

Good piece of information. Thanks ✪ω✪

Educational round proving itself why it is educational

I just used plain old sqrt (with long double) and brute forced the correct value assuming that the precision error is at most +/-10

I used sqrtl then I got accepted B

SpoilerI write binary search this way (after log part), when I am lazy to think)

aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaah im so angry and happy i learnt something. I used sqrt() and not sqrtl() but still AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

This gave me AC with sqrt

CodeUpd: Maybe I Just made 2 mistakes that are Canceling each other

You might get hacked/fst

I tried to hack me now, In Local i got WA but in codeforces i got AC(Unsuccesfull hacking attempt) I think i'm lucky today. I switched to GNU C++20 (64) and got WA too

Testyou are wrong

std::sqrt precision is good enough to work on integers (at least up to long long)

(edit: in c++ 17)

Can anyone give an actual example where you should use binary search instead of std::sqrt? Never had any precision problems for integers with sqrt

Edit: it seems like there are no problems on c++ 17 but when I switch to c++ 20 it fails. Either way, writing binary search for sqrt seems too boring, just use c++ 17

C++ is evolving backwards

i actually had precision issues with c++17 in a previous contest, (this is my alt's submission because that day i could only give first hour of contest)

https://codeforces.com/contest/1737/submission/174985763

you can verify if you replace sqrt with sqrtl this is correct

Then what I said was right

sad story

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