题目链接:Uva 167 思路分析:八皇后问题,采用回溯法解决问题. 代码如下: #include <iostream> #include <string.h> using namespace std; ; int A[MAX_N]; int M[MAX_N][MAX_N]; ; int is_safe( int row, int col ) { ; i < row; ++i ) { if ( A[i] == col ) return false; if ( A[i] + i…

https://vjudge.net/contest/68264#problem/R The Sultan of Nubia has no children, so she has decided that the country will be split into up to k separate parts on her death and each part will be inherited by whoever performs best at some test. It is po…

这道题是典型的八皇后问题,刘汝佳书上有具体的解说. 代码的实现例如以下: #include <stdio.h> #include <string.h> #include <stdlib.h> int vis[100][100];//刚開始wrong的原因就是这里数组开小了,开了[8][8],以为可以.后来看到[cur-i+8]意识到可能数组开小了.改大之后AC. int a[8][8]; int C[10]; int max_,tot; void search_(int…

The Sultan's Successors Description The Sultan of Nubia has no children, so she has decided that the country will be split into up to k separate parts on her death and each part will be inherited by whoever performs best at some test. It is possible…

UVa 167 题意:八行八列的棋盘每行每列都要有一个皇后,每个对角线上最多放一个皇后,让你放八个,使摆放位置上的数字加起来最大. 参考:https://blog.csdn.net/xiaoxiede_wo/article/details/79973171 #include <iostream> #include <cstring> #include <iomanip> using namespace std; ][]; int ans; ][]; void dfs(i…

UVA.839 Not so Mobile ( 二叉树 DFS) 题意分析 给出一份天平,判断天平是否平衡. 一开始使用的是保存每个节点,节点存储着两边的质量和距离,但是一直是Runtime error.也不知道到底是哪里出了问题,后来发现直接判断当前是否平衡,若下面还有节点,接着递归调用dfs判断,这样一来省去了存储节点所需要的空间和时间,效率大大提升. 代码总览 #include <iostream> #include <cstdio> #include <cstring…

the squares thus selected sum to a number at least as high as one already chosen by the Sultan. (For those unfamiliar with the rules of chess, this implies that each row and column of the board contains exactly one queen, and each diagonal contains n…

https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=3270 2017年的第一题. 题意:给出必须要经过的边,找一条经过所有边的最短道路. 一开始一点想法都没有,后来网上看了下才明白是要用dfs和欧拉回路来做的. 欧拉回路是这样说的:如果一个无向图是连通的,且最多只有两个奇点,则一定存在欧拉道路.如果有两个奇点,则必须从其中一个奇点出发,另一个…

博客第一篇写在11月1号,果然die die die die die alone~ 一道不太难的题,白书里被放到排序这一节,半年前用快排A过一次,但是现在做的时候发现可以用字典树加深搜,于是乐呵呵的开始敲了,后来被卡了两天,一直以为算法错了,最后发现是输出答案时忘了回溯,这问题之前没怎么注意过,也算不小的收获. 字典树A了之后换sort来写,没想到快排效率更高,时间减少了一半,在POJ上A了之后重新在UVA上提交,居然WA了,调试半个小时,发现是变长数组的问题,看来UVA上的编译器对c99的支持…

UVA - 524 Prime Ring Problem Time Limit:3000MS     Memory Limit:0KB     64bit IO Format:%lld & %llu Description A ring is composed of n (even number) circles as shown in diagram. Put natural numbers  into each circle separately, and the sum of number…