Update README.md

Author: gouravthakur39

README.md

@@ -52,6 +52,7 @@ These program are written in codeblocks ide for windows. These programs are not
 - [Dice roll with Adjustable sides](https://github.com/gouravthakur39/beginners-C-program-examples/blob/master/DiceRoll.c)
 - [Dynamic 2D Array Using One Pointer](https://github.com/gouravthakur39/beginners-C-program-examples/blob/master/DynamicTwoDArrayUsingOnePointer.c)
 - [Dyanamic 2D Array using Array of Pointer](https://github.com/gouravthakur39/beginners-C-program-examples/blob/master/DynamicTwoDArrayUsingArrayOfPointer.c)
+- [Digital Root of a Number](https://github.com/gouravthakur39/beginners-C-program-examples/blob/master/DigitalRoot.c)
 
 
 # Contributing