Update README.md

Author: Pankajcoder1

README.md

@@ -1,9 +1,11 @@
 # competitive_programming
 Contain file of my [competitive programming](https://en.wikipedia.org/wiki/Competitive_programming) including some platform like..
-- Codeforces
-- Codechef
-- Hackerrank
-- Hackerearth
+- [Codeforces](https://codeforces.com/)
+- [Codechef](https://www.codechef.com/)
+- [Hackerrank](https://www.hackerrank.com/)
+- [Hackerearth](https://www.hackerearth.com/)
+- [CSES](https://cses.fi/problemset/)
+- Facebook hacker cup
 
 
 Executable codes to contest problems in [c++](https://medium.com/sololearn/reasons-to-love-c-11c7c2f23d88)