Codeforces 540 E. Infinite Inversions

题目链接:http://codeforces.com/contest/540/problem/E E. Infinite Inversions time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output There is an infinite sequence consisting of all positive integers in

E. Infinite Inversions time limit per test 2 seconds memory limit per test 256 megabytes input standard input  output standard output There is an infinite sequence consisting of all positive integers in the increasing order: p = {1, 2, 3, ...}. We pe

花了近5个小时,改的乱七八糟,终于A了. 一个无限数列,1,2,3,4,...,n....,给n个数对<i,j>把数列的i,j两个元素做交换.求交换后数列的逆序对数. 很容易想到离散化+树状数组,但是发现那些没有交换的数也会产生逆序对数,但我没有算. 经明神提示, 把没有用到的数字段化成点.然后用树状数组算一下就好了. 然后我用一个数组记录每个点的长度.比如 <1,2><5,6>,1,2,3,4,5,6只有1,2,5,6用到了,那么离散化为1,2,3,4,5,f[1]=

D - Infinite Maze We've got a rectangular n?×?m-cell maze. Each cell is either passable, or is a wall (impassable). A little boy found the maze and cyclically tiled a plane with it so that the plane became an infinite maze. Now on this plane cell (x,

题意:一共n个数,给出其中k个数,要求这n个数的中位数为y,这n个数的和不超过x,补全剩下的n-k个数 先统计给出的k个数里面比中位数小的数, 如果cnt<=n/2,说明中位数还没有出现,把这n/2-cnt个数都补上1,剩下的都补上y 如果cnt>n/2,说明中位数不存在 1 #include<iostream> 2 #include<cstdio> 3 #include<cstring> 4 #include <cmath> 5 #includ

1.题目描述:点击打开链接 2.解题思路:本题要求找出经过若干次交换后的数组中逆序对的个数.可以利用树状数组(BIT)解决.计数时可以分为两部分来分别统计.第一部分是统计位置i右边的所有不在原位置的元素中,小于rk[i]的个数.注意:这一部分统计的都是位置发生过变动的元素.第二部分统计位置i右边中仍在原位置的元素中,小于rk[i]的个数.接下来我们考虑如何快速求解这两部分的个数. 第一部分:因为这部分统计的元素均是不在原位置的元素.因此可以考虑用BIT求解.这是BIT的一个经典运用,务必要理解这

Discription The Bad Luck Island is inhabited by three kinds of species: r rocks, s scissors andp papers. At some moments of time two random individuals meet (all pairs of individuals can meet equiprobably), and if they belong to different species, th

今天唯一的成果就是把上次几个人一起开房打的那场cf补一下. A. Combination Lock 此等水题看一眼样例加上那个配图我就明白题意了,可是手抽没有注释掉freopen,WA了一发. 1 #include <bits/stdc++.h> 2 using namespace std; 3 4 const int maxn = 1000 + 10; 5 6 char s1[maxn], s2[maxn]; 7 8 int main() 9 { 10 int n; cin >>

E. Infinite Inversions time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output There is an infinite sequence consisting of all positive integers in the increasing order: p?=?{1,?2,?3,?...}. We per