While chess problems and such are usually meant for Puzzling Stack Exchange, I thought that this one should be an exception since it’s more relevant IMHO.
Resetting the 50-move rule, i.e. restart the 100 ply cycle, requires either a pawn push or a capture. Checkmate does not restart it of course.
[Title "Geir Sune Tallaksen Østmoe, MatPlus.net Forum 8/14/2013, White To Move"]
[FEN "1K6/2p5/p5pr/q2k3n/P1pPp1rP/1pP1PpPR/1P3P1B/3N3N w - - 0 1"]
Given that White is playing to reset the 50-move rule and Black is trying to avoid it, how many moves will it take to for White to reset the 50-move rule? Or, in layman’s terms, after how many moves can White make a capture or a pawn moves while Black avoids doing or allowing that to happen?