Hello, i am beginner in algorithmic world.So can anyone please suggest me materials for preparing for algorithmic contest , it would be very nice if someone could share links of online material,ebook,etc. and also share their advices/suggestions with me :) And also tell me about various coding contests (like this,codeforces).

Also , basically i know english but you can reply in your own language too as i may google translate it :P

Thankyou in advanced :)