Exercise Four

Sum_Attempt

# Things we'll need:
#   1. Something to keep track of the running total
#   2. Something that goes through the list one number at a time
#   3. Something that adds the current number to the running total
#
# For (3), consider these bits of Ruby:
#   total = 10           # assign the value 10 to the variable "total"
#   total = total + 5    # the value of "total" is now 15
#   total = total + 20   # the value of "total" is now 35
#   total = total + 7    # the value of "total" is now 42
#   total = total - 10   # the value of "total" is now 32 (notice the minus)
#   total = total + 70   # the value of "total" is now 102
 
def sum(list)
   list.inject(0) do |total, num| #From my understanding from various resources, this basically says start at 0 and
       total += num               # add the first item in the list which becomes total, and then the next item is added
    end                           # as num to total. Once completed, from my understanding, .inject has logic that
                                  # tells it to return the value
end 

p sum([1]) 
p sum([0]) 
p sum([-1]) 
p sum([1, -1]) 
p sum([0, 10, 0, 20]) 
p sum([-111, -111, -111]) 
p sum([11,22,33]) 
 
# Questions:
# 1.) How do I get it to return per line, isn't that the point of this exercise? For instance, how would I get it to return
# each value, such as line 35's list "total = 0" on one line, next "total = 0 + 11", next line "total = 11+22".
# I could not find a way to do it like, 'running_total = return item[0], return item[0] + item[1]...item[i]'.

# 2.) Where do you guys go to start when trying to find a method? Is there a method I should be following when I do not
# know where to start? I checked the technical documentation but didn't find it there. I will admit I am not comfortable 
# just yet with reading/comprehending all of it. I then googled 'each loop running total ruby' and looked around stack 
# overflow which had a link to enumerables technical docs which then lead to some experimenting and possible success.