ETA — Blogewoosh #8?

Thank you, but you didn't mention invariants.

Please tell how to approach for problems such as https://codeforces.com/contest/1169/problem/C

Why you don't do analysis of all next educational rounds problems? They are cool to learn topics but sometimes they are hard to understand even with the editorial

I am just going to leave this here.

Can you make a similar video on topics like RMQ and Geometry as many people struggle in those topics?

Finally 1st.

In case of finding maximum in first increasing and then decreasing array if duplicate elements are present how to handle this?

Really great tutorial , I suggest making such tutorials in number theory topics like segmented sieve or search techniques like ternary search.

I have also implemented the code for the problem to find the maximum value in a mountain range . this is my code , can you kindly review my code if there is any bugs ?

https://ideone.com/5YgGqF

Thank you Errichto for the great lecture.

However I'm concerned about binary search on double:

const double target = 1e18;
double L = 0, R = target;
while (R - L > 1e-9) {
    double mid = L + (R - L) / 2;
    if (mid * mid < target)
        L = mid;
    else
        R = mid;
}

I think previous code won't stop, as when L and R get near the sqrt (which is 1000000000), numbers will be large so precision will be low and comparision (R — L > 1e-9) will never be false.

I prefer use L and Sz (size of the interval), instead of L and R as Sz will always get halved each time, so it's guaranteed to stop.

const double target = 1e18;
double L = 0, Sz = target;
while (Sz > 1e-9) {
    double mid = L + Sz / 2;
    if (mid * mid < target)
        L = mid;
    Sz /= 2;
}

We can also limit the iterations by log of the number.

Hi Errichto, When there will be a lecture on dp?

Can someone explain me where to use left+1 and Right -1 or not to use -1 or +1 . Watched the video but couldn't find any solution to this problem :) ;