Educational Codeforces Round 35 (Rated for Div. 2) https://codeforces.com/contest/911 A 模拟 #include<bits/stdc++.h> using namespace std; #define lson l,mid,rt<<1 #define rson mid+1,r,rt<<1|1 #define IT set<ll>::iterator #define sqr(…

[题目链接]: Educational Codeforces Round 35 (Rated for Div. 2) A. Nearest Minimums time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given an array of n integer numbers a0, a1, ..., an -…

B. Two Cakes 传送门:http://codeforces.com/contest/911/problem/B 本题是一个数学问题. 有a个Ⅰ类球,b个Ⅱ类球:有n个盒子.将球放入盒子中,要求: ①所有的球均被放入盒子中: ②每一个盒子中至少有一个球: ③一个盒子里至多只能有一类球. 设将所有的球放入盒子后,每个盒子里至少有x个球.求x的最大值. 由上述规则可知,一个盒子或放入Ⅰ类球,或放入Ⅱ类球.设放入Ⅰ类球的盒子数为i,放入Ⅱ类球的盒子数为j,则:i+j=n. 于是,为使盒子中放入…

A. Nearest Minimums time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given an array of n integer numbers a0, a1, ..., an - 1. Find the distance between two closest (nearest) minimum…

C. Three Garlands time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Mishka is decorating the Christmas tree. He has got three garlands, and all of them will be put on the tree. After that Mi…

B. Two Cakes time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output It's New Year's Eve soon, so Ivan decided it's high time he started setting the table. Ivan has bought two cakes and cut them in…

Nearest Minimums 相同的数里最小的数里的最小距离 Solution Two Cakes Solution Three Garlands 瞎比试 Solution Inversion Counting 先算出来最初逆序对个数,对于每次选择,如果选出的区间里数对个数为偶数个,则其中正序对和逆序对个数可能分别为(奇数+奇数)或(偶数+偶数),此时总的逆序对奇偶性不变:如果选出的区间里数对个数为奇数个,则其中正序对和逆序对个数可能分别为(奇数+偶数)或(偶数+奇数),此时总的逆序对奇偶性…

[链接] 我是链接,点我呀:) [题意] 在这里输入题意 [题解] 排列中交换任意两个数字. 排列的逆序对个数的奇偶性会发生变化. 翻转这个过程其实就是len/2对数字发生交换. 交换了偶数次的话,不变,否则奇偶性发生改变. 先暴力求出一开始的逆序对个数就好 [代码] #include <bits/stdc++.h> using namespace std; const int N = 1500; int n,a[N+10],cnt,now,m; void out(int x){ if (x=…

[链接] 我是链接,点我呀:) [题意] 在这里输入题意 [题解] 直觉题. 感觉情况会很少. 毕竟间隔太大了.中间肯定有一些数字达不到. 有1肯定可以 2 2 x肯定可以 3 3 3也可以 2 4 4也可以. 就这样 [代码] #include <bits/stdc++.h> using namespace std; vector <int> v; int main(){ #ifdef LOCAL_DEFINE freopen("rush_in.txt", &…

[链接] 我是链接,点我呀:) [题意] 在这里输入题意 [题解] 从小到大枚举x. 看看a/x+b/x是不是大于等于n 是的话. 看看是不是两种蛋糕都能凑一堆. 也即x的最大枚举量是min(a,b) 不然可能有多余的a%x没地方放.(因为它都还没有一堆 [代码] #include <bits/stdc++.h> using namespace std; int n,a,b; int main(){ #ifdef LOCAL_DEFINE freopen("rush_in.txt&q…

[链接] 我是链接,点我呀:) [题意] 在这里输入题意 [题解] 找出最小的数字的位置. 最近的肯定是相邻的某对. [代码] #include <bits/stdc++.h> using namespace std; const int N = 1e5; int n; int a[N+10],mi; int main(){ #ifdef LOCAL_DEFINE freopen("rush_in.txt", "r", stdin); #endif io…

Educational Codeforces Round 72 (Rated for Div. 2)-D. Coloring Edges-拓扑排序 [Problem Description] ​ 给你一个有向图,给用最少的颜色给每条边染色,要保证不存在一个环中的所有边都是同一个颜色. [Solution] ​ 用拓扑排序判断图中是否存在环,若图中不存在环,则所有边都是同一种颜色.否则,同一个环中,只要用两种颜色就可以满足题目条件,所以总的颜色数就是两种,对于一个环,一定会存在两种边:1.节点号小…

[Educational Codeforces Round 16]E. Generate a String 试题描述 zscoder wants to generate an input file for some programming competition problem. His input is a string consisting of n letters 'a'. He is too lazy to write a generator so he will manually ge…

[Educational Codeforces Round 16]D. Two Arithmetic Progressions 试题描述 You are given two arithmetic progressions: a1k + b1 and a2l + b2. Find the number of integers x such that L ≤ x ≤ R andx = a1k' + b1 = a2l' + b2, for some integers k', l' ≥ 0. 输入 Th…

[Educational Codeforces Round 16]C. Magic Odd Square 试题描述 Find an n × n matrix with different numbers from 1 to n2, so the sum in each row, column and both main diagonals are odd. 输入 The only line contains odd integer n (1 ≤ n ≤ 49). 输出 Print n lines…

[Educational Codeforces Round 16]B. Optimal Point on a Line 试题描述 You are given n points on a line with their coordinates xi. Find the point x so the sum of distances to the given points is minimal. 输入 The first line contains integer n (1 ≤ n ≤ 3·105)…

[Educational Codeforces Round 16]A. King Moves 试题描述 The only king stands on the standard chess board. You are given his position in format "cd", where c is the column from 'a' to 'h' and dis the row from '1' to '8'. Find the number of moves perm…

Educational Codeforces Round 6 C. Pearls in a Row 题意:一个3e5范围的序列:要你分成最多数量的子序列,其中子序列必须是只有两个数相同, 其余的数只能出现一次. 策略: 延伸:这里指的延伸如当发现1-1如果以最后出现重叠的数为右边界则就表示左延伸,若以1.0.1..0第二个0前一个位置作为右边界就为右延伸: 开始时想是右延伸,考虑到可能只出现一组两个数相同,认为向左延伸会出错,但是直接WA了之后,发现这并不是题目的坑点(其实只需将最后一组改成左右…

Educational Codeforces Round 9 Longest Subsequence 题目描述:给出一个序列,从中抽出若干个数,使它们的公倍数小于等于\(m\),问最多能抽出多少个数,并输出方案与公倍数. solution 枚举每一个数,将它的倍数的答案加一,最大值就是答案. 时间复杂度:\(O(nlogn)\) Thief in a Shop 题目描述:给出\(n\)中物品与它们的价值,每种物品都有无限个,问从中拿出\(m\)个,价值有可能是什么,输出所有的价值. soluti…

Educational Codeforces Round 37 这场有点炸,题目比较水,但只做了3题QAQ.还是实力不够啊! 写下题解算了--(写的比较粗糙,细节或者bug可以私聊2333) A. Water The Garden 题意:给你一个长度为\(n\)的池子,告诉你哪些地方一开始有水, 每秒可以向左和向右增加一格的水, 问什么时候全部充满水.(\(n \le 200\)) 题解:按题意模拟.每次进来一个水龙头,就更新所有点的答案 (取\(min\)).最 后把所有点取个\(max\)就…

Problem   Educational Codeforces Round 60 (Rated for Div. 2) - C. Magic Ship Time Limit: 2000 mSec Problem Description Input Output The only line should contain the minimal number of days required for the ship to reach the point (x2,y2)(x2,y2). If it…

Problem   Educational Codeforces Round 60 (Rated for Div. 2) - D. Magic Gems Time Limit: 3000 mSec Problem Description Input The input contains a single line consisting of 2 integers N and M (1≤N≤10^18, 2≤M≤100). Output Print one integer, the total n…

616A - Comparing Two Long Integers    20171121 直接暴力莽就好了...没什么好说的 #include<stdlib.h> #include<stdio.h> #include<math.h> #include<cstring> #include<iostream> #include<algorithm> using namespace std; string a,b;int sa,sb;…

Educational Codeforces Round 43 (Rated for Div. 2) https://codeforces.com/contest/976 A #include<bits/stdc++.h> using namespace std; #define lson l,mid,rt<<1 #define rson mid+1,r,rt<<1|1 #define IT set<ll>::iterator #define sqr(x)…

Codeforces Educational Codeforces Round 44 (Rated for Div. 2) F. Isomorphic Strings 题目连接: http://codeforces.com/contest/985/problem/F Description You are given a string s of length n consisting of lowercase English letters. For two given strings s an…

Codeforces Educational Codeforces Round 44 (Rated for Div. 2) E. Pencils and Boxes 题目连接: http://codeforces.com/contest/985/problem/E Description Mishka received a gift of multicolored pencils for his birthday! Unfortunately he lives in a monochrome w…

Educational Codeforces Round 63 (Rated for Div. 2)题解 题目链接 A. Reverse a Substring 给出一个字符串,现在可以对这个字符串进行一次翻转,问是否存在一种方案,可以使得翻转后字符串的字典序可以变小.   这个很简单,贪心下就行了. 代码如下: Code #include <bits/stdc++.h> using namespace std; typedef long long ll; const int N = 3e5…

这两道题都需要用到拓扑排序,所以先介绍一下什么叫做拓扑排序. 这里说一下我是怎么理解的,拓扑排序实在DAG中进行的,根据图中的有向边的方向决定大小关系,具体可以下面的题目中理解其含义 Educational Codeforces Round 25  E. Minimal Labels 题目链接:http://codeforces.com/contest/825/problem/E 题意:给你一个有向无环图(DAG),有n个顶点,m条边,顶点的序号分别是1-n,现在给你1-n的数对n个顶点进行赋值…

Educational Codeforces Round 40 F. Runner's Problem 题意: 给一个$ 3 * m \(的矩阵,问从\)(2,1)$ 出发 走到 \((2,m)\) 的方案数 \(mod 1e9 + 7\), 走的规则和限制如下: From the cell (i, j) you may advance to: (i - 1, j + 1) - only if i > 1, (i, j + 1), or (i + 1, j + 1) - only if i <…

Educational Codeforces Round 39 (Rated for Div. 2) G 题意: 给一个序列\(a_i(1 <= a_i <= 10^{9}),2 <= n <= 200000\), 如果至多删除其中的一个数之后该序列为严格上升序列,那么称原序列为几乎严格上升序列. 现在每次将序列中的任意数字变成任意数字,问最少要操作几次才能将序列变成几乎严格上升子序列. 思路: 如果不考虑删除,求让整个序列都变成严格上升子序列的次数 求出\(序列a_i - i\)…