Allowed Digit Multiples
Time limit1sMemory limit128 MB
Count multiples of X within [A,B] whose decimal digits all come from an allowed digit set, with values up to 10^11.
- Level
Hard8 of 10
- Topics
- Dynamic programming, Math, Combinatorics
- Solved
- No attempts yet
Problem
You are given a positive integer X, a range [A, B], and a set of usable digits. Count how many multiples of X between A and B, inclusive, have a decimal representation whose every digit belongs to the given set.
Numbers are considered in their usual decimal representation, so leading zeroes are not allowed.
Input
The first line contains X, A, and B separated by spaces. (1 <= X <= 10^11, 1 <= A <= B <= 10^11)
The second line contains the usable digits in increasing order, with no duplicates.
Output
Print the number of multiples of X between A and B, inclusive, that are made only of the given digits.