A die simulator generates a random number from 1
to 6
for each roll. You introduced a constraint to the generator such that it cannot roll the number i
more than rollMax[i]
(1-indexed) consecutive times.
Given an array of integers rollMax
and an integer n
, return the number of distinct sequences that can be obtained with exact n
rolls. Since the answer may be too large, return it modulo 109 + 7
.
Two sequences are considered different if at least one element differs from each other.
Example 1:
Input: n = 2, rollMax = [1,1,2,2,2,3] Output: 34 Explanation: There will be 2 rolls of die, if there are no constraints on the die, there are 6 * 6 = 36 possible combinations. In this case, looking at rollMax array, the numbers 1 and 2 appear at most once consecutively, therefore sequences (1,1) and (2,2) cannot occur, so the final answer is 36-2 = 34.
Example 2:
Input: n = 2, rollMax = [1,1,1,1,1,1] Output: 30
Example 3:
Input: n = 3, rollMax = [1,1,1,2,2,3] Output: 181
Constraints:
1 <= n <= 5000
rollMax.length == 6
1 <= rollMax[i] <= 15
- Find Missing Observations (Medium)