Whale talk compiling issue

https://www.codecademy.com/courses/learn-c-plus-plus/projects/cpp-whale-talk

I have an issue compiling the code:

#include <iostream>
#include <vector>
#include <string>

int main() {

  std::string input = "turpentine and turtles";

  std::vector<char> vowels = {"a", "e", "i", "o", "u"};

  std::vector<char> result;


  for (int i = 0; i < input.size(); i++) {

      for (int j = 0; j < vowels.size(); j++) {

        if (input[i] == vowels[j]) {

            result.push_back(input[i]);

          if (input[i] == "e" || input[i] == "u") {

            result.push_back(input[i]);

          }
        }
      }
  
  for (int k = 0; k < result.size(); k++) {

    std::cout << result[k];
  }
  }
}

it comes up with error:

whale.cpp: In function ‘int main()’:
whale.cpp:9:54: error: could not convert ‘{"a", "e", "i", "o", "u"}’ from ‘<brace-enclosed initializer list>’ to ‘std::vector<char>’
   std::vector<char> vowels = {"a", "e", "i", "o", "u"};
                                                      ^
whale.cpp:22:27: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
           if (input[i] == "e" || input[i] == "u") {
                           ^~~
whale.cpp:22:46: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
           if (input[i] == "e" || input[i] == "u") {
                                              ^~~

I looked at the github example code and I don’t know what I’m doing wrong.

Double quoting characters instead of single quoting them is going to create issues for most compilers.

so it should be {'a', 'b'} etc.

Strings and string literals are double quoted.

That worked, thanks!