1. Two Sum

2. Add Two Numbers

3. Longest Substring Without Repeating Characters

4. Median of Sorted Arrays

13. Roman to Integer

14. Longest Common Prefix

20. Valid Parantheses

23. Merge K Sorted Lists

24. Swap Nodes in Paris

26. Remove Duplicated from Sorted Arrays

27. Remove Element

28. Implement strStr()

29. Two Integers