摘要：
Alice are given an array A[1..N]A[1..N] with NN numbers. Now Alice want to build an array BB by a parameter KK as following rules: Initially, the arra 阅读全文
摘要：
Bob intends to color the nodes of a tree with a pen. The tree consists of NN nodes. These nodes are numbered 1,2,...,N1,2,...,N. The root of the tree 阅读全文
摘要：
Alice is interesting in computation geometry problem recently. She found a interesting problem and solved it easily. Now she will give this problem to 阅读全文
摘要：
题意：T组样例，给次给出一个N节点的点权树，以及M，问连通块的点权和sum的情况，输出sum=1到M，用0或者1表示。 思路：背包，N^2，由于是无向的连通块，所以可以用分治优化到NlgN。 然后背包可以用bitset优化。注意不要想着背包合并背包，背包只能合并单点。 阅读全文