Beautiful numbers

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 >>继续阅读

X mod f(x)

Problem Description

Here is a function f(x): int f ( int x ) { if ( x == 0 ) return 0; return f ( x / 10 ) + x % 10;} Now, you want to know, in a given interval [A, B] (1 <= A <= B <= 109), how many integer x that mod f(x) equ >>继续阅读

B-number

Problem Description

A 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 143 and 2639 are not. Your task >>继续阅读

不要62

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 >>继续阅读

Bomb

Problem Description

The 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. >>继续阅读