题目链接 \(Description\) 在一个\(n*n\)的二维平面中有两个不相交的整点矩形,每次可以询问两个矩形有几个完全在你给出的一个矩形中.200次询问内确定两个矩形坐标. \(Solution\) 容易想到二分.整个矩形好像不好判断?那就每次二分判断矩形两个点的横纵坐标.次数为 8*26<200. 前四次二分可以确定出一个矩形的位置.然后第二个矩形就可以根据第一个求了. #include <cstdio> #include <cctype> #define gc(…

D. Searching Rectangles 题目连接: http://codeforces.com/contest/714/problem/D Description Filya just learned new geometry object - rectangle. He is given a field consisting of n × n unit cells. Rows are numbered from bottom to top with integer from 1 to…

题目链接 \(Description\) 有一棵\(n\)个点的树.你需要在\(11111\)次询问内确定出这棵树的形态.每次询问你给定两个非空且不相交的点集\(S,T\)和一个点\(u\),交互库会告诉你满足\(x\in S,y\in T\),且\(x\to y\)经过了\(u\)的点对\((x,y)\)的数量. \(n\leq500\). \(Solution\) 不妨假设以\(1\)为根.首先如果想知道\(y\)是否在\(x\)的子树内,询问\(S=\{1\},T=\{y\},u=x\)就…

题目链接: B. Searching Rectangles time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Filya just learned new geometry object — rectangle. He is given a field consisting of n × n unit cells. Rows ar…

题目链接 \(Description\) 有一个长为\(n\)的二进制串,保证\(01\)都存在.你可以询问不超过\(15\)次,每次询问你给出一个长为\(n\)的二进制串,交互库会返回你的串和目标串的不同位的数目.求任意一个\(0\)和\(1\)的位置. \(n\leq 1000\). \(Solution\) 通过\(0...\)和\(1...\)就可以判断出第一个数是什么.然后二分,对每个区间判断是否全为\(0/1\),就可以找到另一个了. 为啥有时候用read()会T.. #includ…

题目链接 \(Description\) 有一个大小为\(k\)的集合\(S\),元素两两不同且在\([1,n]\)内.你可以询问不超过\(60\)次,每次询问你给出\(x,y\),交互库会返回\(\left[\ \min(|x-a|,a\in S)\leq \min(|y-a|,a\in S)\ \right]\)是(TAK)否(NIE)为真.求任意两个一定在集合\(S\)中出现过的数. \(Solution\) 考虑对区间\([l,r]\)二分,若Check(mid,mid+1)==1,则区…

D. Game with modulo time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output This is an interactive problem. Vasya and Petya are going to play the following game: Petya has some positive integer num…

This is an interactive problem. In the output section below you will see the information about flushing the output. On Sunday Leha the hacker took Nura from the house where she lives and went with her to one of the most luxurious restaurants in Vičko…

C - Preparing for the Contest Time Limit:2000MS     Memory Limit:262144KB     64bit IO Format:%I64d & %I64u Submit Status Practice CodeForces 377B Description Soon there will be held the world's largest programming contest, but the testing system sti…

题目链接:Codeforces 484B Maximum Value 题目大意:给定一个序列,找到连个数ai和aj,ai%aj尽量大,而且ai≥aj 解题思路:类似于素数筛选法的方式,每次枚举aj,然后枚举k,每次用二分找到小于k∗aj而且最大的ai,维护答案,过程中加了一些剪枝. #include <cstdio> #include <cstring> #include <algorithm> using namespace std; const int maxn =…