C. Divisibility by Eight Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/550/problem/C Description You are given a non-negative integer n, its decimal representation consists of at most 100 digits and doesn't contain leadin…

题目传送门 /* 数学/暴力:只要一个数的最后三位能被8整除,那么它就是答案:用到sprintf把数字转移成字符读入 */ #include <cstdio> #include <algorithm> #include <cstring> #include <iostream> #include <cmath> #include <vector> using namespace std; ; const int INF = 0x3f3…

A. Two Substrings time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given string s. Your task is to determine if the given string s contains two non-overlapping substrings "AB"…

Codeforces Round #486 (Div. 3) E. Divisibility by 25 题目连接: http://codeforces.com/group/T0ITBvoeEx/contest/988/problem/E Description You are given an integer n from 1 to 10^18 without leading zeroes. In one move you can swap any two adjacent digits in…

题目传送门 /* DFS: 排序后一个一个出发往后找,找到>r为止,比赛写了return : */ #include <cstdio> #include <iostream> #include <cstring> #include <cmath> #include <algorithm> #include <vector> #include <map> #include <queue> #include…

题目传送门 /* 水题:遍历一边先找AB,再BA,再遍历一边先找BA,再AB,两种情况满足一种就YES */ #include <cstdio> #include <iostream> #include <cstring> #include <cmath> #include <algorithm> #include <vector> #include <map> #include <queue> #includ…

Codeforces Round #297 (Div. 2)D. Arthur and Walls Time Limit: 2 Sec  Memory Limit: 512 MBSubmit: xxx  Solved: 2xx 题目连接 http://codeforces.com/contest/525/problem/D Description Finally it is a day when Arthur has enough money for buying an apartment. H…

题意与分析 极简单的数论+思维题. 代码 #include <bits/stdc++.h> #define MP make_pair #define PB emplace_back #define fi first #define se second #define ZERO(x) memset((x), 0, sizeof(x)) #define ALL(x) (x).begin(),(x).end() #define rep(i, a, b) for (repType i = (a); i…

E. Brackets in Implications Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/550/problem/E Description Implication is a function of two logical arguments, its value is false if and only if the value of the first argument is…

D. Regular Bridge Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/550/problem/D Description An undirected graph is called k-regular, if the degrees of all its vertices are equal k. An edge of a connected graph is called a b…

B. Preparing Olympiad Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/550/problem/B Description You have n problems. You have estimated the difficulty of the i-th one as integer ci. Now you want to prepare a problemset for…

A. Two Substrings Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/550/problem/A Description You are given string s. Your task is to determine if the given string s contains two non-overlapping substrings "AB" and "…

A. Two Substrings You are given string s. Your task is to determine if the given string s contains two non-overlapping substrings "AB" and "BA" (the substrings can go in any order). Input The only line of input contains a string s of l…

A. Two Substrings 题意:给一个字符串,求是否含有不重叠的子串"AB"和"BA",长度1e5. 题解:看起来很简单,但是一直错,各种考虑不周全,最后只能很蠢的暴力,把所有的AB和BA的位置求出来,能有一对AB和BA不重叠即可. #include <bits/stdc++.h> using namespace std; ]; vector<int> ab; vector<int> ba; int main() { w…

链接:http://codeforces.com/contest/550/problem/A 这是我第一次玩cf这种比赛,前面做了几场练习,觉得div2的前面几个还是比较水的. 所以看到这道题我果断觉得是拼手速的题啊,结果瞬间就一发WA,连pretest都没通过, 然后开始想,发现没那么简单的样子,很多坑的样子,当我写了2个循环把AB BA 都扫一遍时, 认为考虑周全后,觉得能过了,就交,过了pretest,当时看room里面 大多数还没过A呢,觉得很高兴. 然后学长说这题能叉很多人,我不懂什么…

题目链接:http://codeforces.com/contest/550 A 暴力一发. 代码: #include <iostream> #include <stdio.h> #include <math.h> #include <string> #include <string.h> #include <set> #include <map> #include <vector> #include <…

题意: 给出n个数字,要求在这n个数中选出至少两个数字,使得它们的和在l,r之间,并且最大的与最小的差值要不小于x.n<=15 Problem - 550B - Codeforces 二进制 利用二进制, 第i位为1则加上a[i], 为0则不加, #include<iostream> #include <algorithm> #include <cmath> #include<map> using namespace std; typedef long…

D题:Regular Bridge 乱搞. 构造 这题乱搞一下即可了.构造一个有桥并且每一个点的度数都为k的无向图. 方法非常多.也不好叙述.. 代码例如以下: #include <cstdio> #include <cstring> #include <cmath> #include <queue> #include <stack> #include <map> #include <algorithm> #define…

意甲冠军 到不超过一个更100该整数字符串.采取随机从数间(不能拿). 问:是否有可能被剩下8除尽.假设能,出口YES和任选一个数字的其余病例的. 不能够,输出NO. 思路 想法题. 首先观察到.1000能够整除8. 也就是说我们能够不关心4位数的情况. 仅仅要有可能存在题目说的数.那么它一定能够表示成3位数或更低的位数.那么就好办了,直接枚举就可以. 先看是否有0. 再看是否有8. 接着枚举两位数的情况.最后枚举三位数的情况. 代码 #include <cstdio> #include &l…

题意与分析 稍微复杂一些的思维题.反正这场全是思维题,就一道暴力水题(B).题解直接去看官方的,很详尽. 代码 #include <bits/stdc++.h> #define MP make_pair #define PB emplace_back #define fi first #define se second #define ZERO(x) memset((x), 0, sizeof(x)) #define ALL(x) (x).begin(),(x).end() #define r…

题意与分析 图论基础+思维题. 代码 #include <bits/stdc++.h> #define MP make_pair #define PB emplace_back #define fi first #define se second #define ZERO(x) memset((x), 0, sizeof(x)) #define ALL(x) (x).begin(),(x).end() #define rep(i, a, b) for (repType i = (a); i &…

题意与分析 一道非常坑的水题.分析醒了补. 代码 #include <bits/stdc++.h> #define MP make_pair #define PB emplace_back #define fi first #define se second #define ZERO(x) memset((x), 0, sizeof(x)) #define ALL(x) (x).begin(),(x).end() #define rep(i, a, b) for (repType i = (a…

A. Two Substrings time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given string s. Your task is to determine if the given string s contains two non-overlapping substrings "AB"…

D. Regular Bridge time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output An undirected graph is called k-regular, if the degrees of all its vertices are equal k. An edge of a connected graph is c…

题意 给一个字符串(长度<=10^5).问当中有没有一个"BA"和一个"AB"呢?假设都有而且它们不反复(即ABA不算),输出YES.否则输出NO. 思路 一開始想简单了-.. 我们扫一遍,把全部"AB"字符串中A的索引放入一个vector a,把全部"BA"字符串中B的索引放入还有一个vector b.最后扫一遍两个vector.假设发现一个b的值既不是一个a的值+1,也不是那个a的值-1,那么肯定就存在不反复的&qu…

传送门 题意:给定一个数,可以对其做交换相邻两个数字的操作.问最少要操作几步,使得可以被25整除. 思路:问题可以转化为,要做几次交换,使得末尾两个数为00或25,50,75: 自己一开始就是先for一遍,记录四种可能对于的步数,再对四种可能讨论(有前导0的情况):自己是在数据中,该对了自己的代码, 看了队长和%王宣凯的代码,觉得那才是现场能ac的思路.--暴力交换: #include <iostream> #include <cstdio> #include <algori…

 B. Mike and Fun Time Limit: 20 Sec  Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/548/problem/A Description Mike and some bears are playing a game just for fun. Mike is the judge. All bears except Mike are standing in an n × m grid, there'…

A. Borya and Hanabi Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/442/problem/A Description Have you ever played Hanabi? If not, then you've got to try it out! This problem deals with a simplified version of the game. Ove…

B. Equivalent Strings Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/559/problem/B Description Today on a lecture about strings Gerald learned a new definition of string equivalency. Two strings a and b of equal length are…

C. Amr and Chemistry Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/558/problem/C Description Amr loves Chemistry, and specially doing experiments. He is preparing for a new interesting experiment. Amr has n different type…