Steven D'Aprano wrote: > I just ran your code, and it almost crashed my computer.
When you suspect that a script may consume a lot of memory (the subject might have been a hint) ulimit (bash internal) helps you prevent that your linux machine becomes unresponsive. $ ulimit -v 200000 $ python3 tmp2.py > /dev/null Traceback (most recent call last): File "tmp2.py", line 134, in <module> mresult = DFS(b, 2, 2, mylist, path) File "tmp2.py", line 125, in DFS path = DFS(b, deep-1, maxx, sourceoperators, path) File "tmp2.py", line 129, in DFS b.append([str(i)+str(j) for i,j in zip(aaa, bbb)]) File "tmp2.py", line 129, in <listcomp> b.append([str(i)+str(j) for i,j in zip(aaa, bbb)]) MemoryError -- https://mail.python.org/mailman/listinfo/python-list