These are some LCA (lowest common ancestor) problems. I hope you enjoy them.
I tried to sort them by difficulty. If you know more problems, add it to comments.
208E - Blood Cousins
191C - Fools and Roads
519E - A and B and Lecture Rooms
587C - Duff in the Army
609E - Minimum spanning tree for each edge
178B3 - Greedy Merchants
176E - Archaeology
466E - Information Graph
Hello, A Secret Mission — LOJ , Min Max Roads — LOJ , LCA — SPOJ , Kth Ancestor — HackerRank
Here I found a few LCA / LCA modifications :)
Some basic LCA problems? Which can be solved by only using LCA? By some I mean many please! O_o
Thank you so much for taking the time to compile all these lists.
I really appreciate your work!
504E - Misha and LCP on Tree
LCA + hash
Thanks for gathering all problems with same tag!! I was looking for LCA ones :D
Another LCA problmes:
Qtree spoj : LCA + Heavy-light Decomposition + segment tree
372D - Choosing Subtree is Fun : LCA + sorting + dfs(starting time calculating) + two_pointer (or Heavy-light Decomposition)
342E - Xenia and Tree : LCA + Sqrt Decomposition
342E — Xenia and Tree can be solved by both -decomposition and centroid decomposition.
Centroid decomposition solution
629E - Famil Door and Roads
A great LCA problem from codechef : TOMJERGA
916E - Jamie and Tree
the newest one :)
I wrote code for 191C but I got verdict: wrong answer on test 3. please, tell to me, why my code does not works correctly. link: https://codeforces.com/contest/191/submission/39604271
986E - Prince's Problem
Nice problem :)
http://www.spoj.com/problems/DISQUERY/ this is problem based only on LCA. this problem is from the SPOJ. update: this problem is not based only on lca, sorry for mistake.
https://codeforces.com/contest/1062/problem/E Nice LCA problem ^_^
But Why I am getting WA :(
DFS + LCA + Dual Segment Tree...
Solved in O(n*log(n)^2)
Longest Code in my life but what a nice problem!!!
https://www.hackerrank.com/contests/101hack26/challenges/sherlock-and-queries-on-the-graph (LCA + Bridge finding) :) and thank you so much for your list
Two easy ones and a harder one
Kattis — tourists Kattis — boxes Kattis — pokegene
Thanks for these problem list and i was waited for this
this problem from a recent round
1-Trees and Queries
in the recently contest
csacademy's Identifying-Infected is a LCA tagged problem. How to approach this? Sorry for necro-bumping.
Answer is the number of
cutvertices on the simple path between query vertices in the
Block-Cut Treeof the graph. This can be found in logN time by calculating the LCA of the
LCA problem from the contest just now codeforces.com/contest/1702/problem/G2
Highly recommend))) 786D - Rap God
what a good recommend :D