Codeforces Round #1070 (Div. 2) Hello, codeforces ₍^. .^₎⟆ ------------------ <img src="https://i.ibb.co/9HDfGR5z/155897492717156605.jpg" style="float: right;margin: 0 5% 5%;width: 25.0%;height: 25.0%;"> [user:ABalobanov,2025-12-09], [user:Slamur,2025-12-09] and I are happy to invite you to participate in [contest:2176], which will take place on [contest_time:2176]. This round will be **rated** for all participants with rating below **2100**. You will be given **2 hours** to solve **6 problems**. We are extremely grateful to these wonderful people - The cutest coordinator [user:FairyWinx,2025-12-09]. - [user:KAN,2025-12-09], [user:MikeMirzayanov,2025-12-09] for **Codeforces** and **Polygon** systems. - Our amazing testers: - **<span style="color: black;">R</span><span style="color: red;">ed-black</span>** testing: [user:Um_nik,2025-12-09]. - **<span style="color: red;">Red</span>** testing: [user:A_G,2025-12-09], [user:Wansur,2025-12-09], [user:OG_Matveychick1,2025-12-09], [user:__baozii__,2025-12-09...

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Codeforces Round 1070 (Div.2) Editorial Thank you all for participation! We hope, you enjoyed the problems. ###[problem:2176A] <spoiler summary="Hints"> <spoiler summary="Hint 1"> Which element of the array cannot be removed using the described operations? </spoiler> <spoiler summary="Hint 2"> Under what condition the element $a_j$ **cannot** be removed? </spoiler> </spoiler> <spoiler summary="Solution"> Note that the element $a_1$ cannot be removed using the described operations. In general, the $j$-th element **cannot** be removed if $a_j$ is not less than all elements $a_1 \ldots a_{j - 1}$. Otherwise, among the elements $a_1 \ldots a_{j - 1}$, there will always be an element $a_i > a_j$, which means that $a_j$ can be removed. The constraints are small enough, so for each element, this statement can be checked in $O(n)$ for one check &mdash; resulting in a total of $O(n^2)$ for the test. The idea for solving it in $O(n)$ is as follows: - We will process the elements starting from $a...

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ICPC Amritapuri Practice Session #5 [Team Contest] Announcement Hello Codeforces, **ICPC Amritapuri** Regional will be hosting next team practice round on [CodeDrills](https://codedrills.io/contests/amrita-icpc-practice-session-5) on [Sunday, 28th March 2021](https://www.timeanddate.com/worldclock/fixedtime.html?msg=ICPC+Amritapuri+Practice+Session+%235&iso=20210328T20&p1=438&ah=2&am=30). There will be 5 problems to be solved in 2.5 hours.  **Contest Details** - Contest Link — https://codedrills.io/contests/amrita-icpc-practice-session-5 - Date & Time — [28 Mar 2021, Sunday, 20:00 IST](https://www.timeanddate.com/worldclock/fixedtime.html?msg=ICPC+Amritapuri+Practice+Session+%235&iso=20210328T20&p1=438&ah=2&am=30) - Duration — 2.5 Hours - Will follow standard ICPC scoring system (20 minutes penalty and 1 point per problem) **Registration** - You will need to create a team on the contest page in order to participate. - Team size can be upto ...

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From TLE to AC using magic! When I was solving the problem D from the last contest [Codeforces Round 1070 (Div. 2)](https://mirror.codeforces.com/contest/2176), in the contest i wrote the dp arguments like (vertex v, parent of vertex v), it gave TLE [see my submission](https://mirror.codeforces.com/contest/2176/submission/353184706), and using some optimizations i reduced the dp arguments to just 1 and it was the index of the edge, and same it gave TLE :-( in the contest I was able to optimize this solution using segment tree and binary search and finally it gave AC! but after the contest I just changed a small thing in my first submission instead of having arguments like (vertex v, parent of vertex v), I changed it to (vertex v, the value of the parent of vertex v) and it was passed!!, [see my submission](https://mirror.codeforces.com/contest/2176/submission/353185192) Can anyone tell me how that happened? Thanks!

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Problem Topics Good Day to you! I've been asked to make some topic-wise list of problems I've solved. Even though I couldn't involve all problems, I've tried to involve at least "few" problems at each topic I thought up (I'm sorry if I forgot about something "easy"). I've alredy made such list once anyway I've tried to include more problems now &mdash; so here it is: <spoiler summary="aho"> http://www.spoj.com/problems/ADAJOBS/ URI 2226 (5) //[NICE][NUMBERS][DP] http://www.spoj.com/problems/SUB_PROB/en/ http://mirror.codeforces.com/contest/696/problem/D 8 http://www.spoj.com/problems/AHOCUR/ 5 //Aho-Corassic + DP https://www.codechef.com/problems/LYRC (5) //Sample aho-brute-force http://mirror.codeforces.com/problemset/problem/346/B //Proposed by [user:bradyawn,2019-08-03] </spoiler> <spoiler summary="automat"> 6861 [LA] //CYK UVA 10679 //Suffix Automat http://www.spoj.com/problems/STRMATCH/ //Suffix Automat &mdash; trie might do too http://www.spoj.com/problems/NSUBST...

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Can you hack my solution in [last round 1070] problem F (Omega Numbers) ?? [F. Omega Numbers](https://mirror.codeforces.com/contest/2176/problem/F) [this is my solution](https://mirror.codeforces.com/contest/2176/submission/353146501) `for every element I iterate over different value of omega and iterate over different gcd of element` `and form each gcd I iterate over different multiples of gcd ..why it didnot get tle ??` `it passed in 1218 ms.`

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