24 lines
626 B
C++
24 lines
626 B
C++
#include <cstdio>
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/**
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* 1641. Count Sorted Vowel Strings
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*
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* Given an integer n, return the number of strings of length n that consist only of vowels (a, e, i, o, u) and are lexicographically sorted.
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* A string s is lexicographically sorted if for all valid i, s[i] is the same as or comes before s[i+1] in the alphabet.
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*/
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class Solution {
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public:
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static int countVowelStrings(int n) {
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int ans[5]{1, 1, 1, 1, 1};
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while (--n)
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ans[4] += (ans[3] += (ans[2] += ++ans[1]));
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return ans[0] + ans[1] + ans[2] + ans[3] + ans[4];
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}
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};
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int main() {
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std::printf("%d\n", Solution::countVowelStrings(33));
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return 0;
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}
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