[C++]-1 LINER-EASY TO UNDERSTAND-BEGINNER-SHORT CONCISE-INTERVIEW-WITH EXPLANATION
\n/*\n\nEXPLANATION: [C++]-1 LINER-EASY TO UNDERSTAND-BEGINNER-SHORT CONCISE-INTERVIEW-WITH EXPLANATION\n\nEXPLANATION:\n\nBasically n==1 - 5 combinations. Each
```\n/*\n\nEXPLANATION: [C++]-1 LINER-EASY TO UNDERSTAND-BEGINNER-SHORT CONCISE-INTERVIEW-WITH EXPLANATION\n\nEXPLANATION:\n\nBasically n==1 - 5 combinations. Each ending with a vowel\n\nending with a-5,e-4,i-3,o-2,u-1\nn==2 = 5+4+3+2+1\n\nsimilarly n==3 == 35... 15+ (aa-5 , ae-4, ai-3,ao-2, au-1 and so on), which will lead to binomial coefficient of Binomial coefficient binomial(n,4) = n*(n-1)*(n-2)*(n-3)/24 starting from 5th term\n\nThus follows https://oeis.org/A000332\n*/\n\nclass Solution {\npublic:\n    int countVowelStrings(int n) {\n        return ((n+4)*(n+3)*(n+2)*(n+1))/24;\n    }\n};\n```
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