#include <algorithm>
#include <iostream>

int main()
{
  const char str[] = "Hallo Welt";
  const char vokal[] = "aeiuo";

  const char *pos = std::find_end(str, str+10, vokal, vokal+5);
    
  if (pos != end(str)) 
  {
    std::cout << pos << '\n';
  }
}