Update README.md

Author: soapyigu

README.md

@@ -62,6 +62,7 @@
 [Longest Substring Without Repeating Characters](https://leetcode.com/problems/longest-substring-without-repeating-characters/)| [Swift](./String/LongestSubstringWithoutRepeatingCharacters.swift)| Medium| O(n)| O(n)|
 [One Edit Distance](https://leetcode.com/problems/one-edit-distance/)| [Swift](./String/OneEditDistance.swift)| Medium| O(n)| O(n)|
 [Word Pattern](https://leetcode.com/problems/word-pattern/)| [Swift](./String/WordPattern.swift)| Easy| O(n)| O(n)|
+[Text Justification](https://leetcode.com/problems/text-justification/)| [Swift](./String/TextJustification.swift)| Hard| O(n^2)| O(n)|
 
 ## Linked List
 | Title | Solution | Difficulty | Time | Space |