Intervals 题目连接: http://codeforces.com/gym/100231/attachments Description Start with an integer, N0, which is greater than 0. Let N1 be the number of ones in the binary representation of N0. So, if N0 = 27, N1 = 4. For all i > 0, let Ni be the number…

D. Beautiful numbers time limit per test 4 seconds memory limit per test 256 megabytes input standard input output standard output Volodya is an odd boy and his taste is strange as well. It seems to him that a positive integer number is beautiful if…

D. Beautiful numbers time limit per test 4 seconds memory limit per test 256 megabytes input standard input output standard output Volodya is an odd boy and his taste is strange as well. It seems to him that a positive integer number is beautiful if…

题意:求[L,R](1<=L<=R<=9e18)区间中所有能被自己数位上的非零数整除的数的个数 分析:丛数据量可以分析出是用数位dp求解,区间个数可以转化为sum(R)-sum(L-1)前缀和相减的形式.如果一个数能被所有位上数的最小公倍数(lcm)整除,便是符合要求的数. 但是直接传递一个数n的话,dp数组肯定开不下.那么怎么让其传递的值更小呢. 先了解一个等式: sum%(x*n)%x == sum%x 可以将一个数枚举到第pos位之前的值视作sum,x是所有位上数的lcm.那么我们…

链接: https://vjudge.net/problem/CodeForces-55D 题意: Volodya is an odd boy and his taste is strange as well. It seems to him that a positive integer number is beautiful if and only if it is divisible by each of its nonzero digits. We will not argue with…

Intervals 题目连接: http://codeforces.com/gym/100231/attachments Description 给你n个区间,告诉你每个区间内都有ci个数 然后你需要找一个最小的点集,使得满足这n个区间的条件 Input n 然后li,ri,ci Output 输出最小点集大小 Sample Input 5 3 7 3 8 10 3 6 8 1 1 3 1 10 11 1 Sample Output 6 Hint 题意 题解: 线段树+二分+贪心 首先我们贪心一…

题意:找到[a, b]符合下列要求的数的个数. 1.该数字能被m整除 2.该数字奇数位全不为d,偶数位全为d 分析: 1.dp[当前的位数][截止到当前位所形成的数对m取余的结果][当前数位上的数字是否到达了上限] 2.对于第三维的上限,例如一个数字是54362,那么如果前四位是5436,那么前四位都到达了上限,第五位可以从0枚举所有可能,例如如果第五位是1,那么就没到达上限,如果是6就到达了上限,简而言之,就是个匹配的问题. 需要注意的是,上限不是指第二位数字只能是0~4,第三位数字只能是0~…

题目大意: 求  1(m)到n直接有多少个数字x满足 x可以整出这个数字的每一位上的数字 思路: 整除每一位.只需要整除每一位的lcm即可 但是数字太大,dp状态怎么表示呢 发现 1~9的LCM 是2520 ....也就是说只要对这个数mod2520 剩下的余数能整除lcm就可以整除了.. 计数的时候还有一个技巧,具体见注释 此外这个题还卡常数了,预处理lcm才过了.. 代码如下: #include <iostream> #include <stdio.h> #include<…

题目链接:https://vjudge.net/problem/CodeForces-55D D. Beautiful numbers time limit per test 4 seconds memory limit per test 256 megabytes input standard input output standard output Volodya is an odd boy and his taste is strange as well. It seems to him…

Codeforces 981 D.Bookshelves 题目大意: 给n个数,将这n个数分为k段,(n,k<=50)分别对每一段求和,再将每个求和的结果做与运算(&).求最终结果的最大值. 思路: 将答案ans二进制表示,按位枚举,从最高位i开始,检查ans|(1<<i)是否能够得到,如果能,则ans|=1<<i,向低位继续枚举:不能,就直接继续向低位枚举. 检查 ans|(1<<i)能否得到:每次用DP的方式寻找,dp[i][j]表示将前i个数分为j段…