待思考題單 是男人就过 8 题--Pony.AI 题 https://www.jisuanke.com/contest/1209?from=topalert_link NAIPC 2018 Problem G. Rainbow Graph http://serjudging.vanb.org/?p=1165 Matroid Notes: http://math.mit.edu/~goemans/18433S11/matroid-intersect-notes.pdf