problem1 link 用$f[i][0],f[i][1]$表示从$i$位置开始Alice是先手是否可以胜利,是后手是否可以胜利. problem2link 每次钱数够$price$时可以选择使得$n$或者$k$中较小的一个增加1.最多也就增加$2*10^{6}$次.钱数不够$price$时可以直接算出还要多少次可以够$price$.每一次也可以直接计算出不再变化$n,k$而直接挣够$target$时的次数. problem3 link 如果$k$足够大,最后一定是在某一个区间$[L,R]$…
problem1 link 倒着想.每次添加一个右括号再添加一个左括号,直到还原.那么每次的右括号的选择范围为当前左括号后面的右括号减去后面已经使用的右括号. problem2 link 令$h(x)=\sum_{i=1}^{x}g(i)$,那么答案为$h(R)-h(L-1)$.对于$h(x)$: (1)如果$x\leq K$,那么$h(x)=0$ (2)否则对于$[K+1,x]$之间的所有偶数来说,对答案的贡献为$even+h(\frac{x}{2})-h(\frac{K}{2})$,其中$e…
Problem Statement You are given the ints perimeter and area. Your task is to find a triangle with the following properties: The coordinates of each vertex are integers between 0 and 3000, inclusive. The perimeter of the triangle must be exactly…
Problem Statement The Happy Letter game is played as follows: At the beginning, several players enter the field. Each player has a lowercase English letter on their back. The game is played in turns. In each turn, you select two players with dif…