Hello guys I am trying to do a project about heart rate monitor. I want to count the beats per minute but i can't find any algorithm or pseudo code for it 
so any kind of help is appreciated
syd_xp:
Hello guys I am trying to do a project about heart rate monitor. I want to count the beats per minute but i can't find any algorithm or pseudo code for it
The algorithm depends on the type of sensor you would like to use: analogue sensor, digital sensor, I2C sensor ...
There are 'dumb sensors' which needs clever software to get some values, and there are 'clever sensors' that you just need to read to get the value you want.
syd_xp:
any kind of help is appreciated
Help on every possible sensor worldwide that is (or was) available on the market?
So I'm trying to help you with some pseudo code:
- start timer
- count beats
- after 60 seconds stop counting
- the current count then is your BPM
Easy as that. And the best: This works with ALL TYPES of heartbeat sensors! 
you could take a look at my BPM code that I made for music, it could easily be adapted for your purpose.
http://forum.arduino.cc/index.php?topic=142609.msg1810903#msg1810903
even just reading the opening comments on the logic i used to detect a beat could help you write your own from scratch.