No Repeated Neighbour Digit

Difficulty: 1300 4000 ms 128 MB

digit-dp

Count integers in [L, R] with no two adjacent equal digits.

Input: one line with two integers L and R.

Output: the count in [L, R].

Constraints:

• 1 ≤ L ≤ R ≤ 10¹⁸

Sample Tests

1 25

23

100 130

19

Read the Editorial