Arduino Clapper Project to control different outputs

Using Arduino Sensors
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I am making a Complex Robot with Mega. I wish to control the robot with claps like wise
if i make 1 clap then it should trigger an action [eg: Line following] then if i make 2 claps then it should trigger any other action [eg: Obstacle avoider] . So if any one could help me do this very easily .
I need the code only as i am a 9th grader a newbie to arduino.

<<< I NEED IT FAST >>>>>
I HAVE TO DISPLAY IT IN SCIENCE EXIBITION FOR MY SCHOOL AND MINE IS A REALLY SPECIAL PROJECT
SO 2 DAYS LEFT
<<< FAAST >>>> :fearful:

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