|348|[Design Tic-Tac-Toe](https://leetcode.com/problems/design-tic-tac-toe/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_348.java)| O(1)|O(n) | Medium| Design

|347|[Top K Frequent Elements](https://leetcode.com/problems/top-k-frequent-elements/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_347.java)| O(n)|O(1) | Medium| HashTable, Heap

|346|[Moving Average from Data Stream](https://leetcode.com/problems/moving-average-from-data-stream/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_346.java)| O(1)|O(w)) | Easy| Queue

|344|[Reverse String](https://leetcode.com/problems/reverse-string/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_344.java) | O(n) |O(1) | Easy | String

|343|[Integer Break](https://leetcode.com/problems/integer-break/)|[Solution](../master/src/main/java/com/fishercoder/solutions/IntegerBreak.java)| O(1)|O(1) | Medium| Math

|341|[Flatten Nested List Iterator](https://leetcode.com/problems/flatten-nested-list-iterator/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_341.java)| O(n)|O(n) | Medium| Stack

public String reverseVowels(String s) {

StringBuilder sb = new StringBuilder(s);

Set<Character> vowels = new HashSet();

}

public static void main(String...strings){

String s = "leetcode";

System.out.println(test.reverseVowels(s));

}