Problem Description Teacher Mai is in a maze with n rows and m columns. There is a non-negative number in each cell. Teacher Mai wants to walk from the top left corner (1,1) to the bottom right corner (n,m). He can choose one direction and walk to th…

题意:给一个n*m的矩形,每个格子有一个非负数,求一条从(1,1)到(n,m)的路径(不能经过重复的格子),使得经过的数的和最大,输出具体的方案 思路:对于row为奇数的情况,一行行扫下来即可全部走完得到最大和,对于col为奇数的情况一列列扫即可.对于行和列全部为偶数的情况,将所有格子进行黑白染色,起点和终点的颜色一样,而路径上的颜色是交替的,说明总有一个点不能走到,枚举得到不可到点上的最小值,总和减去就是答案.具体的方案构造方法如下:由于只有一个格子被挖掉不能走,考虑整行或整列的走,走完这个格…

The "travelling salesman problem" asks the following question: "Given a list of cities and the distances between each pair of cities, what is the shortest possible route that visits each city and returns to the origin city?" It is an N…

https://pintia.cn/problem-sets/994805342720868352/problems/1038430013544464384 The "travelling salesman problem" asks the following question: "Given a list of cities and the distances between each pair of cities, what is the shortest possib…

Travelling Salesman Problem Problem's Link: http://acm.hdu.edu.cn/showproblem.php?pid=5402 Mean: 现有一个n*m的迷宫,每一个格子都有一个非负整数,从迷宫的左上角(1,1)到迷宫的右下角(n,m),并且使得他走过的路径的整数之和最大,问最大和为多少以及他走的路径. analyse: 首先,因为每个格子都是非负整数,而且规定每个格子只能走一次,所以为了使和尽可能大,必定是走的格子数越多越好.这样我们就需…

The "travelling salesman problem" asks the following question: "Given a list of cities and the distances between each pair of cities, what is the shortest possible route that visits each city and returns to the origin city?" It is an N…

大致题意:n*m的非负数矩阵,从(1,1) 仅仅能向四面走,一直走到(n,m)为终点.路径的权就是数的和.输出一条权值最大的路径方案 思路:因为这是非负数,要是有负数就是神题了,要是n,m中有一个是奇数.显然能够遍历.要是有一个偶数.能够绘图发现,把图染成二分图后,(1,1)为黑色,总能有一种构造方式能够仅仅绕过不论什么一个白色的点.然后再遍历其它点.而绕过黑色的点必定还要绕过两个白色点才干遍历所有点,这是绘图发现的.所以找一个权值最小的白色点绕过就能够了, 题解给出了证明: ,1)1,而棋盘中…

行数或列数为奇数就能够所有走完. 行数和列数都是偶数,能够选择空出一个(x+y)为奇数的点. 假设要空出一个(x+y)为偶数的点,则必须空出其它(x+y)为奇数的点 Travelling Salesman Problem Time Limit: 3000/1500 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others) Total Submission(s): 747    Accepted Submission(s): 272…

Source: PAT A1150 Travelling Salesman Problem (25 分) Description: The "travelling salesman problem" asks the following question: "Given a list of cities and the distances between each pair of cities, what is the shortest possible route that…

Travelling Salesman Problem Time Limit: 3000/1500 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others) Total Submission(s): 568    Accepted Submission(s): 200 Special Judge Problem Description Teacher Mai is in a maze with n rows and m colum…