Sums gym100753M 同余最短路模板,然而这个东西貌似也可以做去年D1T2 首先我们选择一个模数作为基准,然后剩下的这样连边: 对于一个面值为 x 的硬币 ,当前在 u 这个点(感性理解一下吧) u + x < Mod 这种情况直接从u向 u + x 连一条长度为0的边,表示我们在 0 * M + (u + x) 的时候就已经可以凑出了 u + x > Mod 这种情况下可以 u 向 ( u + x ) mod Mod 连一条长度为1的边,表示通过x的硬币至少在 1 * M + (…

正睿OI国庆DAY2:图论专题 dfs/例题 判断无向图之间是否存在至少三条点不相交的简单路径 一个想法是最大流(后来说可以做,但是是多项式时间做法 旁边GavinZheng神仙在谈最小生成树 陈主力说做法是dfs 首先两个点一定在点双联通分量里 点双是简单环,只有两条,不存在 猜测其他情况存在三条 双联通分量分解 输出情况可以用dfs树判,讨论非树边覆盖情况 内包含 下面分叉连到上面 相交 输出点即可 BFS/例题 BFS树没有跳跃边 计数/动态规划有用吧 树上bfs序好像可以判断距离? 边权…

You are given two integer arrays nums1 and nums2 sorted in ascending order and an integer k. Define a pair (u,v) which consists of one element from the first array and one element from the second array. Find the k pairs (u1,v1),(u2,v2) ...(uk,vk) wit…

UVA - 11997 K Smallest Sums Time Limit: 1000MS   Memory Limit: Unknown   64bit IO Format: %lld & %llu [Submit]   [Go Back]   [Status] Description   Problem K K Smallest Sums You're given k arrays, each array has k integers. There are kk ways to pick…

Backward Digit Sums Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 6350   Accepted: 3673 Description FJ and his cows enjoy playing a mental game. They write down the numbers from 1 to N (1 <= N <= 10) in a certain order and then sum ad…

本题的特点在于两个list nums1和nums2都是已经排序好的.本题如果把所有的(i, j)组合都排序出来,再取其中最小的K个.其实靠后的很多组合根本用不到,所以效率较低,会导致算法超时.为了简便,把nums1和nums2里面的元素写成A1,A2,...,A5, B1,...,B5. 维护一个最小堆.并逐渐往里面push and pop元素. 注意以下几点:1. 如果(Ai, Bj)大于堆顶的元素,那么没有比较把(Ai, Bj)和它之后的元素Push进堆.2. 为了便于管理,解法里其实只维护…

题目 Source http://www.spoj.com/problems/TSUM/ Description You're given a sequence s of N distinct integers.Consider all the possible sums of three integers from the sequence at three different indicies.For each obtainable sum output the number of diff…

2065. Different Sums Time limit: 1.0 secondMemory limit: 64 MB Alex is a very serious mathematician and he likes to solve serious problems. For example, this problem. You are to construct an array of n integers in which the amount of different intege…

题目链接: A. Dreamoon and Sums time limit per test 1.5 seconds memory limit per test 256 megabytes input standard input output standard output Dreamoon loves summing up something for no reason. One day he obtains two integers a and b occasionally. He wan…

[codeforces 509]C. Sums of Digits 试题描述 Vasya had a strictly increasing sequence of positive integers a1, ..., an. Vasya used it to build a new sequence b1, ..., bn, where bi is the sum of digits of ai's decimal representation. Then sequence ai got lo…