Count Vowels Permutation LeetCode solution in Python

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# Runtime: 249 ms (Top 78.97%) | Memory: 19.8 MB (Top 29.73%)
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class Solution:
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    def countVowelPermutation(self, n: int) -> int:
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        # dp[i][j] means the number of strings of length i that ends with the j-th vowel.
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        dp = [[1] * 5] + [[0] * (5) for _ in range(n - 1)]
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        moduler = math.pow(10, 9) + 7
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        for i in range(1, n):
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            # For vowel a
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            dp[i][0] = (dp[i - 1][1] + dp[i - 1][2] + dp[i - 1][4]) % moduler
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            # For vowel e
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            dp[i][1] = (dp[i - 1][0] + dp[i - 1][2]) % moduler
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            # For vowel i
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            dp[i][2] = (dp[i - 1][1] + dp[i - 1][3]) % moduler
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            # For vowel o
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            dp[i][3] = (dp[i - 1][2]) % moduler
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            # For vowel u
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            dp[i][4] = (dp[i - 1][2] + dp[i - 1][3]) % moduler
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        return int(sum(dp[-1]) % moduler)