Upsolves[TTPC2019 Task I] I Hate P 别解一个初等数论问题的朴素解法。read moreUpsolves[TTPC2019 Task I] I Hate P一个初等数论问题的巧妙解法。read moreUpsolvesCow Coupons 的贪心算法正确性证明一个贪心算法的正确性证明。read moreUpsolvesPair XORAnother typical pair-counting problem.read moreUpsolvesarc133_d Range XORA typical pair-counting problem.read moreUpsolvescf_1621d The Winter HikeAn interesting problem.read moreUpsolvesabc235_g Painting Weighted GraphA typical instance of tree DP of merge.read moreUpsolvesabc227_g Divisors of Binomial CoefficientFactorize factorial.read moreUpsolvesabc225_f String CardsA strict weak ordering on nonempty strings.read moreUpsolvesabc214_g Three Permutations一个计数问题。read more