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

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