Alex_McAvoy的博客

【概述】数位 DP 实际是一种计数用的 DP，一般就是统计一个区间 [le,ri] 内满足一些条件数的个数。所求的限定条件往往与数的位数有关，例如：数位之和、指定数码个数、数的大小顺序分组等。题目所给的区间范围往往很大，无法通过暴力枚举来求解，一般是要求把某个区间的符合某种特征的数的个数求出来，因此根据根据 “逐位确定” 的基本思想，将最大数按位分解，然后 dfs 依次判断每一位相应的...

Problem DescriptionA bit is a binary digit, taking a logical value of either 1 or 0 (also referred to as "true" or "false" respectively). And every decimal number has a binary representation which ...

【题目描述】经过了选号和漫长的等待，处女座终于拿到了给小姐姐定制的手环，小姐姐看到以后直呼666！处女座其实也挺喜欢6这个数字的，实际上他做手环的时候选取的k=6。所以他对于包含数码6的数字极其敏感。每次看到像4567这样的数字的时候他的心就像触电了一样，想起了小姐姐。现在你要给处女座展示一系列数字，你想知道他的内心会激动多少次。对于同一个数字，他最多只会激动一次，即如果这个数是66...

Problem DescriptionConsider the decimal presentation of an integer. Let's call a number d-magic if digit d appears in decimal presentation of the number on even positions and nowhere else.For exa...

Problem Descriptionwindy定义了一种windy数。不含前导零且相邻两个数字之差至少为2的正整数被称为windy数。 windy想知道，在A和B之间，包括A和B，总共有多少个windy数？Input包含两个整数，A BOutput一个整数Sample Input1 1025 50Sample Output920思路：设 dp...

Problem DescriptionArcueid likes nya number very much. A nya number is the number which has exactly X fours and Y sevens(If X=2 and Y=3 , 172441277 and 47770142 are nya numbers.But 14777 is not a n...

Problem DescriptionBalanced numbers have been used by mathematicians for centuries. A positive integer is considered a balanced number if:1) Every even digit appears an odd number of times i...

Problem DescriptionCreate a code to determine the amount of integers, lying in the set [ X; Y] and being a sum of exactly K different integer degrees of B.Example. Let X=15, Y=20, K=2, B=2. By thi...

Problem DescriptionThe number 666 is considered to be the occult “number of the beast” and is a well used number in all major apocalypse themed blockbuster movies. However the number 666 can’t alwa...

Problem DescriptionFor a decimal number x with n digits (An An-1 An-2 ... A2 A1), we define its weight as F(x) = An * 2n-1 + An-1 * 2n-2 + ... + A2 * 2 + A1 * 1. Now you are given two numbers A and...

Problem DescriptionA balanced number is a non-negative integer that can be balanced if a pivot is placed at some digit. More specifically, imagine each digit as a box with weight indicated by the d...

Problem DescriptionA wqb-number, or B-number for short, is a non-negative integer whose decimal form contains the sub- string "13" and can be divided by 13. For example, 130 and 2613 are wqb-number...

Problem DescriptionThe counter-terrorists found a time bomb in the dust. But this time the terrorists improve on the time bomb. The number sequence of the time bomb counts from 1 to N. If the curre...

Problem Description杭州人称那些傻乎乎粘嗒嗒的人为62（音：laoer）。杭州交通管理局经常会扩充一些的士车牌照，新近出来一个好消息，以后上牌照，不再含有不吉利的数字了，这样一来，就可以消除个别的士司机和乘客的心理障碍，更安全地服务大众。不吉利的数字为所有含有4或62的号码。例如：62315 73418 88914都属于不吉利号码。但是，61152虽然含有6和2，但...

题目给出一段区间a-b，统计这个区间内0-9出现的次数。比如 10-19，1出现11次（10,11,12,13,14,15,16,17,18,19,其中11包括2个1)，其余数字各出现1次。输入两个数a,b（1 <= a <= b <= 10^18)输出输出共10行，分别是0-9出现的次数输入样例10 19输出样例1111111...