OJ Board

I keep noticing that people claim there is an O(n^3) algorithm
for solving problem 108. I cannot see how that can be when there
are (n(n+1)/2)^2 = O(n^4) possible rectangles on an nxn board.
Even if you knew all the sums of the rectangles and didn't need to compute them,
you still had to iterate ...

I've noticed that many people have been concerned with this problem,
so I thought I'd contribute with a (big) hint on avoiding TLE:

DON'T STORE THE BINARY STRING, YOU DON'T NEED TO!

Let's say that you would like to compress the binary string -
what is the essential information that you need in ...

OK, thanks for the tip. Just another thing about PE. I've experienced
PE for one problem when I wrote a new line after the last output, and then got it fixed when I removed it. But, to the contrary, I've also experienced PE for another problem when I didn't write a newline after the last output, and ...

Fixed the problem. I just had to remove the newline after the last field.

--
Tore Nedretvedt

Look at the response i got after submitting the solution:

[BEGIN]
Your C++ program has solved Ok the problem 10189 (Minesweeper)
in 0.018 seconds with low memory spent.
Congratulations!

Warning: Your program would get a Presentation Error in a true contest.
The 24-hours judge interpretes it as an ...