Find the number of unique words consisting of lowercase alphabets only of length N that can be formed with at-most K contiguous vowels.
Example 1:
Input:
N = 2
K = 0
Output:
441
Explanation:
Total of 441 unique words are possible
of length 2 that will have K( =0) vowels
together, e.g. "bc", "cd", "df", etc are
valid words while "ab" (with 1 vowel) is
not a valid word.
Example 2:
Input:
N = 1
K = 1
Output:
26
Explanation:
All the english alphabets including
vowels and consonants; as atmost K( =1)
vowel can be taken.
Your Task:
You don't need to read input or print anything. Your task is to complete the function kvowelwords() which takes an Integer N, an intege K and returns the total number of words of size N with atmost K vowels. As the answer maybe to large please return answer modulo 1000000007.
Expected Time Complexity: O(NK)
Expected Auxiliary Space: O(NK)
Constraints:
1 ≤ N ≤ 1000
0 ≤ K ≤ N

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