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Python Python Basics (2015) Letter Game App Letter Game Refinement

For loop sum = 0 i = 0 for i in range(10): sum = sum + i print sum

Can you pls explain me what is happing in this loop

Steven Parker
Steven Parker
231,236 Points

It's hard to tell what the code is doing without the punctuation and indentation.

Use the instructions for code formatting in the Markdown Cheatsheet pop-up below the "Add an Answer" area. :arrow_heading_down:   Or watch this video on code formatting.

sum = 0
i = 0
for i in range(10):
  sum = sum + I
  print sum

1 Answer

Steven Parker
Steven Parker
231,236 Points

I'm guessing you meant to write little "i" instead of capital "I", and forgot to put the parentheses around the argument to "print". So here's a corrected version with comments:

sum = 0             # start with "sum" at 0
i = 0               # and "i" at 0
for i in range(10): # make "i" go from 0 to 9 while doing the rest
  sum = sum + i     # increase "sum" by the value of "i"
  print(sum)        # print out what "sum" is at each step

So the loop will repeat 10 times, the first time "sum" and "i" will both be 0 so it will print "0". The next time 0 + 1 will be "1", then 1 + 2 will be "3", and so on.

You should see these 10 outputs while it runs: 0, 1, 3, 6, 10, 15, 21, 28, 36, 45.

Thanks a million.