Sothan

HUD 5323 Solve this interesting problem dfs剪枝搜索，重构线段树 Have you learned something about segment tree? If not, don’t worry, I will explain it for you.Segment Tree is a kind of binary tree, it can be defined as this:- For each node u in Segment Tree, u has

POJ 2386 Due to recent rains, water has pooled in various places in Farmer John's field, which is represented by a rectangle of N x M (1 <= N <= 100; 1 <= M <= 100) squares. Each square contains either water

HDU 5167 Following is the recursive definition of Fibonacci sequence:Fi=01Fi−1+Fi−2i = 0i = 1i > 1Now we need to check whether a number can be expressed as the product of numbe

HDU 5339 There is an integer a and n integers b1,…,bn. After selecting some numbers from b1,…,bn in any order, say c1,…,cr, we want to make sure that a mod c1 mod c2 mod… mod cr=0 (i.e., a will become the remai

HDU 1010 The doggie found a bone in an ancient maze, which fascinated him a lot. However, when he picked it up, the maze began to shake, and the doggie could feel the ground sinking. He realized that the bone

HDU 1518 Given a set of sticks of various lengths, is it possible to join them end-to-end to form a square?

POJ 1915 Knight Moves Background Mr Somurolov, fabulous chess-gamer indeed, asserts that no one else but him can move knights from one position to another so fast. Can you beat him?

HDU 2717 Catch That Cow Farmer John has been informed of the location of a fugitive cow and wants to catch her immediately. He starts at a point N (0 ≤ N ≤ 100,000) on a number line and the cow is at a point K

HDU 1240 Asteroids! You're in space.You want to get home.There are asteroids.You don't want to hit them.

DFS（depth first search）：深度优先搜索，即一种有一定策略的枚举 核心：递归 特点： 1. 一搜到底，不通则返 2. 平等遍历，只看方向 3. 只求可行，不求最优 4. 效率过低 DFS伪代码： depthFirstSearch(v) { Label vertex v as reached. for(

SPOJ SERGRID Grid BFS搜索算法 You are on an nxm grid where each square on the grid has a digit on it. From a given square that has digit k on it, a Move consists of jumping exactly k squares in one of the four cardinal directions. A move cannot go beyond the e

RescueProblem DescriptionAngel was caught by the MOLIGPY! He was put in prison by Moligpy. The prison is described as a N * M (N, M Angel's friends want to save Angel. Their task is: app

HUD Crazy Bobo 树上dfs Bobo has a tree,whose vertices are conveniently labeled by 1,2,...,n.Each node has a weight wi. All the weights are distrinct.A set with m nodes v1,v2,...,vm is a Bobo Set if:- The subgraph of his tree induced by this set is connecte

POJ 1979 There is a rectangular room, covered with square tiles. Each tile is colored either red or black. A man is standing on a black tile. From a tile, he can move to one of four adjacent tiles. But he c