题目链接:http://codeforces.com/contest/797 A题 题意:给出两个数n, k,问能不能将n分解成k个因子相乘的形式,不能输出-1,能则输出其因子: 思路:将n质因分解,若质因子数目对于k则可行,随便将其组合成k个因子即可,反之则不行: 代码: #include <bits/stdc++.h> using namespace std; const int MAXN=1e5; int a[MAXN]; int main(void){ ; cin >> n…

A. k-Factorization 题目大意:给一个数n,求k个大于1的数,乘积为n.(n<=100,000,k<=20) 思路:分解质因数呗 #include<cstdio> #define MN 100000 ],an; int main() { int n,k,i; scanf("%d%d",&n,&k); ;k>&&n>;++i)&&n%i==;--k,n/=i)a[++an]=i; )*pu…

A. k-Factorization 题意:给你一个n,问你这个数能否分割成k个大于1的数的乘积. 题解:因为n的取值范围很小,所以感觉dfs应该不会有很多种可能-- #include<bits/stdc++.h> using namespace std; long long n; int k; vector<int> ans; void dfs(int x,long long now,int st){ if(x==k&&now==n){ for(int i=0;i…

这场edu蛮简单的…… 连道数据结构题都没有…… A.随便质因数分解凑一下即可. #include<bits/stdc++.h> #define N 100005 using namespace std; int a[N],cnt,k,x,n; int main(){ scanf("%d%d",&n,&k); ;k>&&n>;i++) &&n%i==;--k,n/=i)a[++cnt]=i; ){puts(;} ;…

A. k-Factorization 题意:将n分解成k个大于1的数相乘的形式.如果无法分解输出-1. 思路:先打个素因子表,然后暴力判,注意最后跳出的条件. int len,a[N],b[N]; void init() { memset(a,-1,sizeof(a)); a[0]=a[1]=0; memset(b,0,sizeof(b)); len=0; for(int i=2; i<N; i++) if(a[i]) { b[len++]=i; if(N/i<i) continue; for…

Description Petya recieved a gift of a string s with length up to 105 characters for his birthday. He took two more empty strings t and u and decided to play a game. This game has two possible moves: Extract the first character of s and append t with…

Description You are given sequence a1, a2, ..., an of integer numbers of length n. Your task is to find such subsequence that its sum is odd and maximum among all such subsequences. It's guaranteed that given sequence contains subsequence with odd su…

Description Given a positive integer n, find k integers (not necessary distinct) such that all these integers are strictly greater than 1, and their product is equal to n. Input The first line contains two integers n and k (2 ≤ n ≤ 100000, 1 ≤ k ≤ 20…

传送门 题意 给出n个数,q个询问,每个询问有两个数p,k,询问p+k+a[p]操作几次后超过n 分析 分块处理,在k<sqrt(n)时,用dp,大于sqrt(n)用暴力 trick 代码 #include<cstdio> int n,a[100100],p,k,q,dp[100100][350]; int main() { scanf("%d",&n); for(int i=1;i<=n;++i) scanf("%d",a+i);…

Educational Codeforces Round 17 A. k-th divisor 水题,把所有因子找出来排序然后找第\(k\)大 view code //#pragma GCC optimize("O3") //#pragma comment(linker, "/STACK:1024000000,1024000000") #include<bits/stdc++.h> using namespace std; function<voi…

[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)…

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(…

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\(序列a_i - i\)…

Educational Codeforces Round 48 (Rated for Div. 2) C. Vasya And The Mushrooms 题目链接:https://codeforces.com/contest/1016/problem/C 题意: emmm,说不清楚,还是直接看题目吧. 题解: 这个题人行走的方式是有一定的规律的,最后都是直接走到底,然后从另外一行走回来.并且通过画图观察,会发现他走到格子的时间会有一定的规律. 所以就维护几个前缀和就行了,从1到n枚举一下,还要…