Update readme

Author: geekayush

Day1-HelloWorld/main.c Day1-HelloWorld/C++/main.cDay1-HelloWorld/main.c renamed to Day1-HelloWorld/C++/main.c

@@ -1 +1,12 @@
-My day-wise collection of [30daysofcode](https://www.hackerrank.com/domains/tutorials/30-days-of-code?filters%5Bstatus%5D%5B%5D=unsolved&badge_type=30-days-of-code) challange of HackerRank
+# 30daysofcode
+##### What is this?
+The repository covers all the basic topics of programming languages. Try a new challenge every day for 30 days. By the end of the month, you'll go from newbie to expert.
+##### Index
+[Day 1 - Hello, World.](https://github.com/geekayush/30daysofcode/tree/master/Day1-HelloWorld)
+##### How to contribute?
+If you can write any specific program in some other languange, then write your program, make sure it passes all the test cases as specified in the readme of each task and submit a PR.
+The program:
+- must be tab indented
+- must not use complicated methods
+___
+Reference [HackerRank](https://www.hackerrank.com/domains/tutorials/30-days-of-code)