1082: [SCOI2005]栅栏 Time Limit: 10 Sec  Memory Limit: 162 MBSubmit: 2247  Solved: 952[Submit][Status][Discuss] Description 农夫约翰打算建立一个栅栏将他的牧场给围起来,因此他需要一些特定规格的木材.于是农夫约翰到木材店购 买木材.可是木材店老板说他这里只剩下少部分大规格的木板了.不过约翰可以购买这些木板,然后切割成他所需 要的规格.而且约翰有一把神奇的锯子,用它来锯木板,不会产…

Given a binary tree, find the largest subtree which is a Binary Search Tree (BST), where largest means subtree with largest number of nodes in it. Note:A subtree must include all of its descendants.Here's an example: 10 / \ 15 / \ \ 1 8 7 The Largest…

http://www.lydsy.com/JudgeOnline/problem.php?id=1082 (题目链接) 题意 给出m块木柴,以及n块木板,要求将m块木柴做木板,要求将木柴切割成与木板一样的长度,问最多可以做成几块木板. Solution 今日考题.乍一看,好像可以二分,然而并不会check,于是码了个贪心,10分mdzz.. 正解:二分+搜索. 每次二分答案mid后,对每块木板进行搜索,枚举用那根木柴去进行切割.没想到剪枝这么强大,这都可以搜过去.. 剪枝1:一开始将不符合条件的…

Can you solve this equation? Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 7156    Accepted Submission(s): 3318 Problem Description Now,given the equation 8*x^4 + 7*x^3 + 2*x^2 + 3*x + 6 == Y…

Can you solve this equation? Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 7493    Accepted Submission(s): 3484 Problem Description Now,given the equation 8*x^4 + 7*x^3 + 2*x^2 + 3*x + 6 == Y,…

题目传送门 题意:问使得sum (k^i) = n || n -1 (1 <= i <= r) 的min (r*k)组合的r和k  分析:r的最大不会超过40,枚举r,二分搜索k.注意会爆long long,所以上界需要优化.r = 2开始上界就小于1e6,cyd将后面的范围也求出来了,其实1e6就够用了. 这水题卡了我好久,没有很好分析题目,做不出来就有种无力感,开始烦躁起来.还是题目做得少了,如果这种题做多了,可能看一眼就能做出来了. /**************************…

还是写一下,二分搜索好了 这道题开数组比较坑... 二分,需要注意边界问题,例如:左闭右闭,左闭右开,否则查找不到or死循环 先上AC代码 #include<iostream> #include<cstdio> #include<cstring> #include<algorithm> using namespace std; struct Ch{ char a[12]; char b[12]; }; int cmp(const void *aa,const…

Description Demy has n jewels. Each of her jewels has some value vi and weight wi. Since her husband John got broke after recent financial crises, Demy has decided to sell some jewels. She has decided that she would keep k best jewels for herself. Sh…

题意:给出三种操作 0 e:将e放入容器中 1 e:将e从容器中删除,若不存在,则输出No Elment! 2 a k:搜索容器中比a大的第k个数,若不存在,则输出Not Find! 思路:树状数组+二分搜索,具体见代码吧. #include <iostream> #include <stdio.h> #include <string.h> #include <algorithm> /* AC 树状数组+二分搜索 题意:给出三种操作 0 e:将e放入容器中…

Yougth的最大化 时间限制:1000 ms | 内存限制:65535 KB 难度:4 描述 Yougth现在有n个物品的重量和价值分别是Wi和Vi,你能帮他从中选出k个物品使得单位重量的价值最大吗? 输入 有多组测试数据 每组测试数据第一行有两个数n和k,接下来一行有n个数Wi和Vi. (1<=k=n<=10000) (1<=Wi,Vi<=1000000) 输出 输出使得单位价值的最大值.(保留两位小数) 样例输入 3 2 2 2 5 3 2 1 样例输出 0.75 来源 Yo…