题目链接:https://codeforces.com/contest/1263/problem/C 题意:给你一个数字n,求n/k有多少个不同的数 思路:首先K大于n时,n/k是0.然后k取值在1到n之间的时候进行二分即可求解. 举个例子,比如n = 11,那么k分别取值1 2 3 4 5 6 7 8 9 10 11时候,n/k是 11 5 3 2 2 1 1 1 1 1 1,因为n/k这组数据是具有单调性的,那么我们就可以在n/k这个取值范围内二分查找,每次查找到的不同的取值存起来,最终输出…

题目链接:https://codeforces.com/contest/1263/problem/D 题意:有n个小写字符串代表n个密码,加入存在两个密码有共同的字母,那么说这两个密码可以认为是同一个集合,可以互相破解,先求有多少个不同集合的密码 思路:简单的并查集.首先一共有26个字母,对于每个密码,我们合并其所涵盖的字母,例如密码1:abcd,那么abcd合并起来,含有abcd的任意密码都同属于一个集合,所有我们把n个密码串先做一次合并.最终再扫一遍所有的密码串,用set维护集合的个数,最终…

题目链接:https://codeforces.com/contest/1263/problem/E 题意:一个编译器,每次输入一些字符,R表示光标右移,L表示光标左移,然后有一些左括号(  和 右括号 ),每次会询问当前输入的数据的括号是否合法,如果不合法输出-1,如果合法输出最大合法的括号对数,合法的括号就是()这种形式的. 思路:大致思路是用线段树维护区间一个区间前缀和,初始化前缀和为0.遇到单点更新,(让管辖区间+1,)就让管辖区间-1,,判断是否是合法括号需要判断区间最小值是否为0,且…

题意:给你一个整数n,求所有n/k的值(k∈{1,2,3...,n,.......}). 题解:最简单的方法是用枚举1~sqrt(n),把除数和商放进set中,就能直接水过,但后来看其他人的题解了解到了一种新方法:分块. 1,2,3,4,5,6,7,8,9,10. 10,5,3,2,2,1,1,1,1,1. 从k=1开始枚举,我们发现每个n/k的值都会对应一个区间,那么我们可以利用n/(n/k)来得到这个区间的最右边,且下次枚举一定是从n/(n/k)+1开始的. e.g:当k=5时,n/k=2,…

Codeforces Round #603 (Div. 2) A. Sweet Problem A. Sweet Problem time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output You have three piles of candies: red, green and blue candies: the first pile…

C. Everyone is a Winner! On the well-known testing system MathForces, a draw of n rating units is arranged. The rating will be distributed according to the following algorithm: if k participants take part in this event, then the n rating is evenly di…

链接: https://codeforces.com/contest/1263/problem/C 题意: On the well-known testing system MathForces, a draw of n rating units is arranged. The rating will be distributed according to the following algorithm: if k participants take part in this event, t…

tag里有二分,非常的神奇,我用暴力做的,等下去看看二分的题解 但是那个数组的大小是我瞎开的,但是居然没有问题233 #include <cstdio> #include <cmath> #include <cstring> using namespace std; const int N = 1e7; int c[N]; int main() { int t; scanf("%d", &t); while (t--) { int n; sc…

http://codeforces.com/contest/716/problem/D 题目大意:给你一些边,有权值,权值为0的表示目前该边不存在,但是可以把0修改成另外一个权值.现在,我们重新建路,问让s-t的最短路能否刚好是L? 思路:暴力修改即可... //看看会不会爆int!数组会不会少了一维! //取物问题一定要小心先手胜利的条件 #include <bits/stdc++.h> using namespace std; #define LL long long #define AL…

http://codeforces.com/problemset/problem/677/D 题目大意: 给你一个n*m的图,上面有p种钥匙(p<=n*m),每种钥匙至少有一个,期初所有为1的钥匙都是可拿的,拿到了该钥匙以后(假设该钥匙的val是v)就可以拿v+1种类的钥匙.问最后拿到第p个钥匙最少走多少步?(钥匙为p种类的只有一种) 思路:官方题解貌似是二维线段树的,不过这题可以用另外一个方法来优化. 首先假设我们目前在的颜色的c,我们要到c+1颜色的格子里面去,如果单纯的对于每种颜色c跑一次…

C. New Year and Rating time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Every Codeforces user has rating, described with one integer, possibly negative or zero. Users are divided into two d…

传送门 感觉脑子还是转得太慢了QAQ,一些问题老是想得很慢... A. Sweet Problem 签到. Code /* * Author: heyuhhh * Created Time: 2019/11/29 22:36:19 */ #include <iostream> #include <algorithm> #include <vector> #include <cmath> #include <set> #include <ma…

E. Editor The development of a text editor is a hard problem. You need to implement an extra module for brackets coloring in text. Your editor consists of a line with infinite length and cursor, which points to the current character. Please note that…

D. Secret Passwords One unknown hacker wants to get the admin's password of AtForces testing system, to get problems from the next contest. To achieve that, he sneaked into the administrator's office and stole a piece of paper with a list of n passwo…

链接: https://codeforces.com/contest/1263/problem/E 题意: The development of a text editor is a hard problem. You need to implement an extra module for brackets coloring in text. Your editor consists of a line with infinite length and cursor, which point…

链接: https://codeforces.com/contest/1263/problem/D 题意: One unknown hacker wants to get the admin's password of AtForces testing system, to get problems from the next contest. To achieve that, he sneaked into the administrator's office and stole a piec…

链接: https://codeforces.com/contest/1263/problem/B 题意: A PIN code is a string that consists of exactly 4 digits. Examples of possible PIN codes: 7013, 0000 and 0990. Please note that the PIN code can begin with any digit, even with 0. Polycarp has n (…

链接: https://codeforces.com/contest/1263/problem/A 题意: You have three piles of candies: red, green and blue candies: the first pile contains only red candies and there are r candies in it, the second pile contains only green candies and there are g ca…

A. Sweet Problem (找规律) 题目链接 大致思路: 有一点瞎猜的,首先排一个序, \(a_1>a_2>a_3\) ,发现如果 \(a_1>=a_2+a_3\) ,那么答案肯定是 \(a_2+a_3\) ,然后发现发现规律当 \(a_2==a_3\) 的时候,还可以贡献 \((a_1+a_2+a_3)/2\) 的答案,所以只要 \(a_1\) 和 \(a_2\) 减掉一个值就可以了. B. PIN Codes (暴力) 题目链接 大致思路: 可以知道,存在一个数字不同的pi…

F. Economic Difficulties 题目链接: https://codeforces.com/contest/1263/problem/F 题目大意: 两棵树,都有n个叶子节点,一棵树正着放,一棵树倒着放,叶子节点从左到右对应装置1,2,3,4...n,问最多能删掉多少条边,使得装置能与两棵树任意一个根节点1相连. 解题思路: mp[ i ][ j ]是装置 i 到 j 这段区间删除这段连续区间所能删除的最大边数,两个图分开看,算出每一个图中如果不连通这段区间对应的叶子节点所能删除…

E. Editor 题目链接: https://codeforces.com/contest/1263/problem/E 题目大意: 输入一个字符串S1含有‘(’ , ‘)’ , ‘R’ , ‘L’ 以及其他字符.根据这个字符串,得到相应的字符串S2.起始idx=1即S2的初始坐标,然后从左到右读取S1,当遇到'L',idx减小1(当无法左移的情况下idx不减小),当遇到'R',idx增加1,当读取到其他字符时,将idx这个位置上的字符更新为读取到的新的字符.然后输出每一步得到的字符串S2最大…

http://codeforces.com/contest/1263/problem/E 题意:求合法的括号序列 #include<bits/stdc++.h> using namespace std; typedef long long ll; #define lson root<<1,l,midd #define rson root<<1|1,midd+1,r #define pb push_back const int inf=0x3f3f3f3f; const…

这套题我只写了a, b, c..  对不起,是我太菜了. A:思路:就是直接简化为一个矩阵按照特定的步骤从一个顶角走到与之对应的对角线上的顶角.如图所示. 解释一下特定的步骤,就像马走日,象走田一样.你的步骤只能走(x-a, y-b), (x+a, y-b), (x-a, y+b), (x+a, y+b)这几种. 思路:假设高度为h, 宽度为w. 则如果 h%b==0&& w%a==0时,则一定能走到角落里. 还有一种走法:就是先是正常的碰撞,最后几下就斜着走.这样的规律就是 h/b%2=…

1017C The Phone Number: 构造数列使得LIS和LDS的和最小,定理已知LIS=L,LDS=n/L的向上取整,根据样例可以得到设置L=根号n,构造方法如样例 截断法构造,不用考虑边界: Show an example of n=22: "' 19 20 21 22 15 16 17 18 11 12 13 14 7 8 9 10 3 4 5 6 1 2 "' int tmp = sqrt(n); ,j,o=n;i<=n;i+=tmp) { ,n);j>=…

已经是水到一定程度了QAQ- Code: #include<cstdio> #include<algorithm> #include<cstring> using namespace std; const int maxn = 105; int tp[maxn], idx[maxn], n,m, spare[maxn], cnt; bool cmp(int i,int j) { return i > j;} inline bool check(int val) {…

F. Economic Difficulties An electrical grid in Berland palaces consists of 2 grids: main and reserve. Wires in palaces are made of expensive material, so selling some of them would be a good idea! Each grid (main and reserve) has a head node (its num…

B. PIN Codes A PIN code is a string that consists of exactly 4 digits. Examples of possible PIN codes: 7013, 0000 and 0990. Please note that the PIN code can begin with any digit, even with 0. Polycarp has n (2≤n≤10) bank cards, the PIN code of the i…

A. Sweet Problem the first pile contains only red candies and there are r candies in it, the second pile contains only green candies and there are g candies in it, the third pile contains only blue candies and there are b candies in it. Each day Tany…

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#include<bits/stdc++.h> using namespace std; #define int long long signed main(){ int _; cin>>_; while(_--){ ];; ;i<=;i++){ cin>>a[i];add+=a[i]; } sort(a+,a++); ; ]-a[]; ]>=cha){ a[]-=cha; ; ans=a[]+a[]/; cout<<ans<<'\n…