Given a string of lowercase English letters and an integer of the substring length, determine the substring of that length that contains the most vowels. Vowels are in the set $\{a,e,i,o,u\}.$ If there is more than one substring with the maximum number of vowels, return the one that starts at the lowest index. If there are no vowels in the input string, return the string 'Not found!$\text{'}$ without quotes.

Example $1$

$s=$ 'caberqiitefg'

$k=5$

The substring of length $k=5$ that contains the maximum number of vohels is 'erqii' with $3$ vowels.

The final answer is 'erqii'.

Example $2$

$s=$ 'aeiouia'

$k=3$

All of the characters are vowels, so any substring of length $3$ will have $3$ vowels. The lowest index substring is at index $0,$ 'aei'.

Function Description

Complete the function findSubstring in the editor below.

findSubstring has the following parameters:

Returns:

string: a string containing the final answer

Constraints

$1$ length$($s$)2**{10}^5$

$1k$ length$($s$)$

Input Format For Custom Testing

Sample Case $0$

Sample Input

$\backslash$table$[[$STDIN$,,$Function$],[-----,,-----],[$azerdii$,,s={?}^{\text{'}}$ azerdii'$],[,,k=5$