generic_placeholder_name's blog

By generic_placeholder_name, history, 2 months ago, In English

During the Vietnamese team's participation in APIO 2021, we had a large submission queue during our last 2 or so hours, which made it impossible to get the verdict of our submissions.

For me in particular, and for many people in my team, this directly resulted in a big loss of points. For me, I lost 23 points in problem 2 due to an array bounds bug and 31 points in problem 3 due to a bug in subtask 2 (my code for 3 and 4 was correct, but I put it after subtask 2.) These bugs would probably have been fixable had I been able to see the results of my submissions.

The organizers did give us 30 more minutes, but during that time the queue was still blocked anyway.

I am aware that very little can be done at this point on the part of the APIO organizers, but I am still posting this to make people aware of this issue that we encountered. Hopefully there will be something that the organizers can do so that we could have a better experience.

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By generic_placeholder_name, history, 7 months ago, In English

I am pretty sure that during Educational Codeforces Round 100 (Rated for Div. 2), buihoatpt2k3 copied code from huyhoangk36chv.

buihoatpt2k3's behavior is quite suspicious in general — he (?) submitted all his code during the last 30 minutes, and his code is heavily obfuscated.

We see, however, that after running the preprocessor (gcc -E) on the code, we get code that is strikingly similar to that of huyhoangk36chv.

For example, take 1463A - Dungeon. Here's huyhoangk36chv's code: 101515478. And here's the de-obfuscated code from buihoatpt2k3: 101775980.

Same deal for problem D: 101562763, 101776426.

I think this is pretty good evidence that these users cheated and copied code from each other, and as such, call for their participation in the contest to be voided.

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By generic_placeholder_name, history, 3 years ago, In English

I am trying to submit a code on Codeforces, but I always get compilation errors. My computer does just fine. Here is the code:

var s, tmp: ansistring;
        i, j, c: integer;

function elim(var s: ansistring): ansistring;

var i: integer;
for i:=1 to length(s) do
        if s[i]='(' then elim:=elim+s[i]
        else if elim[length(elim)]='(' then delete(elim, length(elim), 1);

readln(s); tmp:=elim(s); c:=0;
if (tmp<>'((') and (tmp<>'))') then writeln(0)
else if tmp='((' then
        i:=0; s:=s+'0';
        while (s[i+1]='(') and (s[i+2]=')') do i:=i+2;
        for j:=i+2 to length(s) do
                if s[j]='(' then c:=c+1;
else begin
        i:=length(s)+1; s:='0'+s;
        while (s[i-2]='(') and (s[i-1]=')') do i:=i-2;
        for j:=i-2 downto 1 do
                if s[j]=')' then c:=c+1;

And here are the comp errors:

Invocation failed [COMPILATION_ERROR]
Can't compile file:
Target OS: Win32 for i386
Compiling program.pas
program.pas(11,36) Error: Operator is not overloaded: "elim(var AnsiString):AnsiString;" + "Char"
program.pas(12,22) Error: Illegal qualifier
program.pas(12,22) Error: Type mismatch
program.pas(12,58) Error: Type mismatch
program.pas(34,4) Fatal: There were 4 errors compiling module, stopping
Fatal: Compilation aborted
Error: C:\Programs\FPC\bin\i386-Win32\ppc386.exe returned an error exitcode

It seems that Codeforces' FPC does not allow adding char and string. How do I resolve this?

P.S. I use FPC 3.0.4.

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