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12 May - 11:47 am

Working again now.

10 May - 4:05 pm

Hello, sorry for the late answer, in fact yes there is an issue with the mail, we will try to fix it quickly. Thanks for reporting

7 May - 6:07 pm

Hi there is a issue for the challenfe Email (number 21). I don't receive a mail on any of them: gmail, hotmail, yahoo. do i fail or is it the challenge ?

28 Feb - 10:35 am

Yes we fixed it

27 Feb - 10:00 pm

Thank you, just validated contest22. The solution checker seems to have been fixed.

27 Feb - 8:40 am

Yes several solutions are accepted of course. I will check one of your answers

26 Feb - 7:51 pm

No 500 error, but the solutions I'm submitting can be verified to be correct. It can't be that only one configuration is accepted, right? - as there are multiple correct configurations for each problem.

26 Feb - 5:54 pm

contest 22 is not concerned by the issue I found, and seems to be working (I suppose you don't have 500 error on this one ?). Your solutions are indeed rejected, but I did not check them yet

26 Feb - 3:25 pm

The validation for contest 22 also seems to be wrong (it's not accepting solutions that are clearly correct). I submitted bug report yesterday.

26 Feb - 9:59 am

Ok I fixed the issue It is higly possible that other challenges are impacted, so don't hesitate to tell meif you encounter this again. Thank you for reporting

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Contests list :: Multimedia :: Image color (56)


ID : 56
Points : 11
Validations :
Challenge page
Report a bug


It is required to be able to solve the challenge base64 in order to solve this challenge.

This challenge is quite simple. We give you an image which contains only one color in the variable img_b64.
You have to return the color of the image, more exactly the red, green and blue parts respectively in the variables r, g and b.

For example, for this image :

You should return
r = 23
g = 119
b = 100


Name Type Description
Variables to get
img_b64Stringchar*The image, in png, encoded in base64
Variables to send back
rIntegerintThe red part of the image color
gIntegerintThe green part of the image color
bIntegerintThe blue part of the image color