Find the common characters among words in an array

commonChars.swift

/*:
Given an array A of strings made only from lowercase letters,
return a list of all characters that show up in all strings within the list (including duplicates).
For example, if a character occurs 3 times in all strings but not 4 times,
you need to include that character three times in the final answer.

You may return the answer in any order.
 
```
Example 1:

Input: ["bella","label","roller"]
Output: ["e","l","l"]
Example 2:

Input: ["cool","lock","cook"]
Output: ["c","o"]
*/

func commonChars(_ A: [String]) -> [String] {
    var resultDict = [Character:Int]()
    for word in A {
        for char in word {
            resultDict[char] = (resultDict[char] ?? 0) + 1
        }
    }
    var resultArr = [String]()
    for (char, count) in resultDict {
        if count >= A.count {
            resultArr.append("\(char)")
        }
    }
    return resultArr
}

var kenny = ["kenny", "many", "sadly"]
commonChars(kenny)

input
["bella","label","roller"]
Output
["l","e"]
Expected
["e","l","l"]

Really close! Try to get it down to two for loops