数学Min-max 容斥Min-max 容斥 maxS=∑T⊆S(−1)∣T∣−1minT\max{S}=\sum_{T\subseteq S}{(-1)^{|T|-1}\min{T}}maxS=T⊆S∑(−1)∣T∣−1minT minS=∑T⊆S(−1)∣T∣−1maxT\min{S}=\sum_{T\subseteq S}{(-1)^{|T|-1}\max{T}}minS=T⊆S∑(−1)∣T∣−1maxT