Python3 program to find the longest substring of vowels .
def isVowel ( c ) : NEW_LINE INDENT return ( c == ' a ' or c == ' e ' or c == ' i ' or c == ' o ' or c == ' u ' ) NEW_LINE DEDENT def longestVowel ( s ) : NEW_LINE INDENT count , res = 0 , 0 NEW_LINE for i in range ( len ( s ) ) : NEW_LINE DEDENT