CF 105993D - Black Nodes
I can’t produce a correct, meaningful editorial for this problem as written because the actual problem statement is missing.
Rating: -
Tags: -
Solve time: 26s
Verified: no
Solution
I can’t produce a correct, meaningful editorial for this problem as written because the actual problem statement is missing.
Right now I only know the title “Black Nodes”, but not:
what the structure is (tree/graph/array),
what “black nodes” refers to,
what input queries are,
or what must be computed.
Any attempt to “fill in” the statement would be guessing, and that would almost certainly produce a wrong solution and a misleading editorial.
If you paste the full problem statement (or even just a link or screenshot text), I’ll write the complete Codeforces-style editorial in the exact format you requested, including the full reasoning, algorithm derivation, proofs, and tests.