I don't know whether to ask here or not but ..
I started practicing in topcoder today.
1)While solving a problem of 250 points i got 240.3 and another question of 250 points i got 83? why so?
Does it means partial marking ?(means topcoder gives partial marks or not)
http://help.topcoder.com/data-science/competing-in-algorithm-challenges/the-practice-rooms/
Why don't you just read the guide given on the topcoder website instead of waiting for other people to answer your questions ?
its about practicing not in rooms,i was using https://arena.topcoder.com/ and searching a problem and solving it
the same system is applicable to both contest and practice.
i asked because it when i submitted a code it gave some points,but when i did system testing it said it failed .Does that mean my code is wrong?
It is mentioned in the link I shared. Just read the guide given on topcoder otherwise there would be hundreds of trivial doubts that you would be posting here.
Yes, it means your code is wrong. Every time you submit, you receive points, whether in practice mode or in a real contest. You can submit an empty code and you'll still receive points. If you fail the system test, you'll lose those points. And the amount of points you get depends on how fast you submit.
the points are given with the assumption that you passed the given test cases in the problem, and then you can test your code with the rest of the test cases in the system test.