time limit per test2 seconds memory limit per test256 megabytes inputstandard input outputstandard output You are given a string s, consisting of lowercase English letters, and the integer m. One should choose some symbols from the given string so th…

题目链接 可以发现 十进制4 对应 二进制100 十进制16 对应 二进制10000 十进制64 对应 二进制1000000 可以发现每多两个零,4的次幂就增加1. 用string读入题目给定的二进制数字,求出其长len,当len为奇数时,第一位为1,后面的位数如果都为0,则输出len,如果有一个不为0,则输出len+1: 当len为偶数时,则输出len.(之所以这样输出是因为题目给定4的次幂是从0开始的) #include<iostream> #include<string> #…

time limit per test1 second memory limit per test256 megabytes inputstandard input outputstandard output Arthur has bought a beautiful big table into his new flat. When he came home, Arthur noticed that the new table is unstable. In total the table A…

time limit per test2 seconds memory limit per test256 megabytes inputstandard input outputstandard output Gerald got a very curious hexagon for his birthday. The boy found out that all the angles of the hexagon are equal to . Then he measured the len…

time limit per test1 second memory limit per test256 megabytes inputstandard input outputstandard output Vanya is doing his maths homework. He has an expression of form , where x1, x2, -, xn are digits from 1 to 9, and sign represents either a plus '…

time limit per test4 seconds memory limit per test256 megabytes inputstandard input outputstandard output Anton likes to play chess. Also, he likes to do programming. That is why he decided to write the program that plays chess. However, he finds the…

[题目链接]:http://codeforces.com/problemset/problem/29/B [题意] 一辆车; 让从A开到B; 然后速度是v; (只有在信号灯前面才能停下来..否则其他时候只能维持v的速度) (如果在红绿灯前,刚好从绿灯变成红灯,不能走,但如果从红灯变成绿灯,则可以走) 告诉你A到信号灯的距离l,以及A.B之间距离d; 以及绿灯红灯交替的时间;g和r; 问你从A到B需要花费多少时间; [题解] 一开始ans=d/v; 看看到达信号灯的时间是不是整数; 不是整数的话;…

[codeforces 415D]Mashmokh and ACM 题意:美丽数列定义:对于数列中的每一个i都满足:arr[i+1]%arr[i]==0 输入n,k(1<=n,k<=2000),问满足[数列长度是k && 数列中每一个元素arr[i]在1~n之间 && 数列中元素可以重复]的数列有多少个?结果对10^9+7取余 解题思路:dp[i][j]表示长度是j,最后一位是i的种数 if(kk%i==0) dp[kk][j+1]+=dp[i][j] #inc…

题目链接: http://codeforces.com/problemset/problem/691/D 题目大意: 给一个1到N的排列,M个操作(1<=N,M<=106),每个操作可以交换X Y位置上的数字,求可以得到的最大字典序的数列. 题目思路: [搜索][并查集] 这题可以用搜索或者并查集写,都能过. 把位置分成若干块,每一块里面的位置都是可以被这一块里另一个位置经过若干次调换的(类似强连通,位置可达). 然后把每一块位置里的 位置按从小到大排序,位置上的值按从大到小排序,依次填入位置…

题目链接: http://codeforces.com/gym/100526 http://acm.hunnu.edu.cn/online/?action=problem&type=show&id=11674&courseid=0 题目大意: N个学生M道题(1<=N<=12,1<=M<=30),每道题只有正误两种选项(0 1),每个学生的答题情况和正确题数已知,求标准答案可能有多少种. 如果标准答案只有一种则输出标准答案,否则输出解的个数. 题目思路: […