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// c is a char
auto isLowercaseVowel = (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u');
auto isUppercaseVowel = (c == 'A' || c == 'E' || c == 'I' || c == 'O' || c == 'U');
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bool is_vowel(char c){
if(c=='a'||c=='e'||c='i'||c=='o'||c=='u') return true;
return false;
}