APIO 2021 Grading System

An instance of Contest Management System (CMS) modified for APIO 2021 will be used as the grading system.


Grading will be performed on Amazon Web Services’ c5.metal Elastic Compute Cloud (EC2) instances with the following specifications:

  • OS: Ubuntu 20.04
  • Processor: Intel(R) Xeon(R) Platinum 8275CL
    • Clock speed set to 2.7 GHz (Intel® Turbo Boost Technology disabled)
    • Hyper-threading disabled
    • 2 cache ways of the L3 cache dedicated to each CPU core used for grading
  • Each execution of a submission will be assigned to a separate physical CPU core


The exact commands used for compilation will be shown on the grading system. With the exception of certain task types, the compilation command will generally be of the following format:

  • C++ (gcc 9.3.0): /usr/bin/g++ -DEVAL -std=gnu++17 -O2 -pipe -static -s -o ${task} grader.cpp ${task}.cpp