标签: 数位DP

「AtCoder 138F」Coincidence

Given are integers L and R. Find the number, modulo 109+710^9+7, of pairs of integers (x,y)(LxyR)(x,y) (L≤x≤y≤R) such that the remainder when y is divided by x is equal to y[mbox]XORxy[mbox]XORx.

「HDU 4734」 F(x)

For a decimal number x with n digits (A nA n-1A n-2 ... A 2A 1), we define its weight as F(x) = A n * 2 n-1 + A n-1 * 2 n-2 + ... + A 2 * 2 + A 1 * 1. Now you are given two numbers A and B, please calculate how many numbers are there between 0 and B, inclusive, whose weight is no more than F(A).

「HDU 2089」 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。