Explanation needed for this Ruby challenge -

i need understanding code:

def simpleadding(num)   sum = 0   (num + 1).times |x|     sum = sum + x   end   return sum end  simpleadding(12) #=> 78 simpleadding(140) #=> 9870 

i not sure of method. why method written way is? why sum on first line set 0? , why sum = sum + x used on third line?

in ruby, def keyword delimits start of method, in case named simpleadding. takes 1 argument (in parentheses) named num.

in method body, variable sum given initial value of 0.

the line containing (num + 1).times |x| tells ruby execute code between do , end keywords set number of times (an iterator), in case num + 1. remember, num represents value received in form of argument when method called.

on next line, variable sum (initialized 0 @ beginning of method) assigned value of plus x.

next line, our iterator ends.

finally, return value stored inside of variable sum.

and, end of our method.

enjoy learning ruby!