Since Kattis uses PyPy for Python 3, there are big performance differences in the problemtools image which uses python3. Using pypy3 in a Docker image will more accurately reflect how the problem will perform in the Kattis system, so I changed the Dockerfile.icpc to support this.
This change depends on the PyPy PPA, but as it's blessed by the PyPy developers I don't see that as an issue.
Since Kattis uses PyPy for Python 3, there are big performance differences in the problemtools image which uses python3. Using pypy3 in a Docker image will more accurately reflect how the problem will perform in the Kattis system, so I changed the Dockerfile.icpc to support this.
This change depends on the PyPy PPA, but as it's blessed by the PyPy developers I don't see that as an issue.