Update README.md

Author: rajatag03

README.md

@@ -1 +1,15 @@
-# Leetcode-Challenge
+# Leetcode-Challenge
+
+# April Leetcoding Challenge 2021
+
+Day | Name of Problem | Leetcode Link | Video Link 
+--- | :---: | :---: | --- 
+1 | Palindrome Linked List | https://leetcode.com/problems/palindrome-linked-list/ | https://youtu.be/Ll9ZbXaXqlQ 
+2 | Ones and Zeroes | https://leetcode.com/problems/ones-and-zeroes/ | https://youtu.be/qkUZ87NCYSw
+3 | Longest Valid Parentheses | https://leetcode.com/problems/longest-valid-parentheses/ | https://youtu.be/VdQuwtEd10M
+4 | Design Circular Queue | https://leetcode.com/problems/design-circular-queue/ | https://youtu.be/Q2YhZ6Pq0GQ
+5 | Global and Local Inversions | https://leetcode.com/problems/global-and-local-inversions/ | https://youtu.be/1QlP6cVLrII
+6 | Minimum Operations to Make Array Equal | https://leetcode.com/problems/minimum-operations-to-make-array-equal/ | https://youtu.be/9aGx9hoIBjI
+7 | Determine if String Halves Are Alike | https://leetcode.com/problems/determine-if-string-halves-are-alike/ | https://youtu.be/752uISt9sCs
+8 | Letter Combinations of a Phone Number | https://leetcode.com/problems/letter-combinations-of-a-phone-number/ | https://youtu.be/Ydur1aYALc4
+9 | Verifying an Alien Dictionary | https://leetcode.com/problems/verifying-an-alien-dictionary/ | https://youtu.be/jK5a8T9q4pc