Frequently Asked Questions Answered
Unoffical English Version
1. What is UOJ?
2. How to upload the avatar when I signed in?
UOJ doesn't store avatars. It is annoying to upload an avatar for every site, isn't it? UOJ supports Gravatar, use it please! Gravatar is a global avatar storing service. Your avatar will be associated with your email address. In many sites like Wordpress and many Online Judge Systems like Vijos and Contest Hunter, if you fill in the email address correctly, your avatar will be shown at once.
3. The judging environment of UOJ?
The judging environment is Linux, on Ubuntu 14.04, 64-bit system.
C++ compiler is g++ 4.8.4. The command to compile your code is
g++ code.cpp -o code -lm -O2 -DONLINE_JUDGE. If you choose C++11, we will add
-std=c++11 to the compile command.
C compiler is gcc 4.8.4. The command to compile your code is
gcc code.c -o code -lm -O2 -DONLINE_JUDGE.
Pascal compiler is fpc 2.6.2. The command to compile your code is
fpc code.pas -O2.
The JDK Version of Java7 is jdk-7u76. The command to compile your code is
The JDK Version of Java8 is jdk-8u31. The command to compile your code is
Python will compile to optimized Byte-code file
.pyo first. Supporting versions of Python are Python 2.7 and 3.4.
4. Why it doesn't stack overflow when I recurse $10^7$ times?
That's right! Unless under special circumstances, The size of stack is same as the memory limit of the problem when judging a program on UOJ.
5. How to use the blog system?
6. How to test the interactive problems locally?
Hmmm... It's a good question. This kind of problems usually give you a header file to include, and a source file, the grader, implementing the interfaces. It seems that many of you aren't familiar with compiling more than one source file at the same time.
g++ -o code grader.cpp code.cpp
gcc -o code grader.c code.c
Otherwise, you can copy the content of grader completely and paste it after your
include statement. It also works!
What? You are the cutest Pascal contestant? The problem gives you a grader as usual. You should make a Pascal unit and the grader will use your unit. So you only need to name your source file the unit name +
And for Pascal:
Then we are finished!
7. Contact Information
If you want to host a problem or hold a competition, discover a bug, or have suggestions for UOJ, you can contact us through the following ways:
Contacts vfleaking by UOJ Message.
Mail to firstname.lastname@example.org.
You can also join our QQ group. The group id is 197293072, and the group name is Universal OJ Users Group.