Dch19990825的博客

1245F. Daniel and Spring Cleaning(数位DP)题目链接：传送门题意：给出l,r​l,r​l,r​，让求满足a∈[l,r],b∈[l,r]​a\in[l,r],b\in[l,r]​a∈[l,r],b∈[l,r]​ 且a⊕b=a+b​a⊕b=a+b​a⊕b=a+b​ 的(a,b)​(a,b)​(a,b)​对数。思路：如果a⊕b=a+ba⊕b=a+ba⊕b=a+...

J - 吉哥系列故事――恨7不成妻单身!　　依然单身！　　吉哥依然单身！　　DS级码农吉哥依然单身！　　所以，他生平最恨情人节，不管是214还是77，他都讨厌！　　　　吉哥观察了214和77这两个数，发现：　　2+1+4=7　　7+7=72　　77=711　　最终，他发现原来这一切归根到底都是因为和7有关！所以，他现在甚至讨厌一切和7有关的数！什么样的数和7有关呢？如果一...

B - XHXJ’s LISdefine xhxj (Xin Hang senior sister(学姐))If you do not know xhxj, then carefully reading the entire description is very important.As the strongest fighting force in UESTC, xhxj grew up...

G - B-numberA 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-numbers, but 14...

F - Balanced NumberA 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 dig...

E - Round NumbersThe cows, as you know, have no fingers or thumbs and thus are unable to play Scissors, Paper, Stone’ (also known as ‘Rock, Paper, Scissors’, ‘Ro, Sham, Bo’, and a host of other names...

C - 不要62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，但不是62连号，所以不属于不...

A - Beautiful numbersVolodya 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. ...