Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib/python2.7/py_compile.py", line 117, in compile
    raise py_exc
py_compile.PyCompileError:   File "/w/foo.py", line 6
    if c == b :ans++
                   ^
SyntaxError: invalid syntax

自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。