Hey Guy's , thanks for the help you're doing for me.

So, How can I write this C programming using for I think.

An alternating sequence : 1 - 1/2 + 1/3 - 1/4 ....... (-1)^n+1(1/n).

Also , how can I draw a triangle using for or while or any other statement.

Thanks for the help , I'm you'll help me with this,please.