problem1 link 直接模拟即可. problem2 link 首先,网关一定是安装在client与server之间的链路上.而不会安装在client与client之间的链路上.对于一条路径c1->c2->c3->c4->s,且不存在任何一个其他的client使得c4到该client存在链路且该client可以到达s.假设c1->c2之间的链路安装了,那么c4->s之间的链路还要安装.所以只需要在c4->s之间的链路安装即可. 所以所有的安装位置一定是在c…
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…
