题意: 给定一个序列,对于q个询问:(L,R)之间有几个逆序对?序列元素个数上限1000,q上限10万.仅1测试例子. 思路: [L,R]的逆序对数量可以这么算,假设L<=K<R,将区间拆成两部分,那么[L,k]中的逆序对要算上, (k,R]中的逆序对也要算上,还有一些逆序对假设为(l,r),l在左部分,r在右部分.则应该是3部分来构成,设3部分为A,B,C,那么ans=A+B+C . 而如果将k移到最右边,比如k=R-1,那么区间拆成[L,k]和(K,R],而(K,R]其实就只有R一个元素,…

Dylans loves sequence Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://acm.hdu.edu.cn/showproblem.php?pid=5273 Description Dylans得到了N个数a[1]...a[N].有Q个问题,每个问题形如(L,R)他需要求出L−R这些数中的逆序对个数.更加正式地,他需要求出二元组(x,y)的个数,使得L≤x,y≤R且x<y且a[x]>a[y] Input 第一行有两个数N和Q…

题目连接 http://acm.hdu.edu.cn/showproblem.php?pid=5273 Dylans loves sequence Description Dylans is given $N$ numbers $a[1]....a[N]$ And there are $Q$ questions. Each question is like this $(L,R)$ his goal is to find the “inversions” from number $L$ to n…

题目链接: hdu:http://acm.hdu.edu.cn/showproblem.php?pid=5273 bc:http://bestcoder.hdu.edu.cn/contests/contest_chineseproblem.php?cid=604&pid=1002 Dylans loves sequence  Accepts: 250  Submissions: 806  Time Limit: 2000/1000 MS (Java/Others)  Memory Limit:…

题意:给出n个数,再给出q个询问,求L到R的逆序对的个数 先自己写的时候,是每次询问都重新插入来求sum(r)-sum(l) 果断T 后来还是看了别人的代码---- 预处理一下,把所有可能的区间的询问都求出来(1000*1000), 然后询问就是O(1)了 然后想自己这样写超时,是因为询问太多了---- #include<iostream> #include<cstdio> #include<cstring> #include <cmath> #includ…

题意:给出一个0≤N≤1018,求其二进制中有几处是具有1的,假设相连的1只算1处,比如1101011就是3处. 思路:一个个数,当遇到第一个1时就将flag置为1:当遇到0就将flag置为0.当遇到1时,flag=0就统计,当flag=1时就不统计. #include <bits/stdc++.h> #define LL long long using namespace std; int main() { int t; LL n; cin>>t; while(t--) { ci…

Dylans loves tree Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 131072/131072 K (Java/Others)Total Submission(s): 1444    Accepted Submission(s): 329 Problem Description Dylans is given a tree with N nodes. All nodes have a value A[i].Nodes…

Hdu 5274 Dylans loves tree (树链剖分模板) 题目传送门 #include <queue> #include <cmath> #include <cstdio> #include <cstring> #include <cstdlib> #include <iostream> #include <algorithm> #include <vector> #define ll long…

Hdu 5806 NanoApe Loves Sequence Ⅱ(双指针) Hdu 5806 题意:给出一个数组,求区间第k大的数大于等于m的区间个数 #include<queue> #include<cmath> #include<cstdio> #include<cstring> #include<cstdlib> #include<iostream> #include<algorithm> #define ll l…

题目连接 http://acm.hdu.edu.cn/showproblem.php?pid=5272 Dylans loves numbers Description Who is Dylans?You can find his ID in UOJ and Codeforces.His another ID is s1451900 in BestCoder. And now today's problems are all about him. Dylans is given a number…