mid
Description
Problem A

http://54.64.29.164:32384/

Hint
gcc version 4.8.2 (Ubuntu 4.8.2-19ubuntu1)
gcc -O2 -static source.c
Read input from stdin and write output to stdout.
Single test case in each file, but test several times on multiple file.

It's a CTF challange, you may need a interesting trick to solve it.
Both setrlimit & cgroup is used.
(memory.limit_in_bytes, memory.swappiness, RLIMIT_AS)

No temp file is allowed. In fact, it's chroot to an read-only empty directory.
No socket, IPC, so you can't send the test data out.
Number of process limit to 8.
All syscall is allowed.

You need to STEAL MORE MEMORY, but how? where?