Count Sorted Vowel Strings: Python, 1-D DP
python\nclass Solution:\n    def countVowelStrings(self, n: int) -> int:\n        a = [1] * 5\n        for _ in range(1, n):\n            for i in range(1, 5):\
```python\nclass Solution:\n    def countVowelStrings(self, n: int) -> int:\n        a = [1] * 5\n        for _ in range(1, n):\n            for i in range(1, 5):\n                a[i] += a[i-1]\n        return sum(a)\n```
['Dynamic Programming', 'Python']