prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  Different behaviour of argmax
  I found the behaviour of `argmax` is different between `numpy` and `cupy` if the array has `0` in its shape and `axis` argument is used. I don't know whether this behaviour is intended or not.
  
  ```
  np.empty((0, 1)).argmax(axis=1)  # array([], dtype=int64)
  cupy.empty((0, 1)).argmax(axis=1)
  ---------------------------------------------------------------------------
  ValueError                                Traceback (most recent call last)
  <ipython-input-9-a5737d72bcba> in <module>()
  ----> 1 cupy.empty((0, 1)).argmax(axis=1)
  
  cupy/core/core.pyx in cupy.core.core.ndarray.argmax (cupy/core/core.cpp:17701)()
  
  cupy/core/core.pyx in cupy.core.core.ndarray.argmax (cupy/core/core.cpp:17556)()
  
  cupy/core/reduction.pxi in cupy.core.core.simple_reduction_function.__call__ (cupy/core/core.cpp:52697)()
  
  ValueError: zero-size array to reduction operation cupy_argmax which has no identity
  ```
  
  I used cupy 2.0.0a1.
  
  --- END ISSUE ---
  
  Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
  --- BEGIN FILES ---
  Path: `cupy/logic/truth.py`
  Content:
  ```
  1 def all(a, axis=None, out=None, keepdims=False):
  2     # TODO(okuta): check type
  3     return a.all(axis=axis, out=out, keepdims=keepdims)
  4 
  5 
  6 def any(a, axis=None, out=None, keepdims=False):
  7     # TODO(okuta): check type
  8     return a.any(axis=axis, out=out, keepdims=keepdims)
  9
  ```
  --- END FILES ---
  
  Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.
  
  Here is an example:
  
  ```diff
  diff --git a/examples/server_async.py b/examples/server_async.py
  --- a/examples/server_async.py
  +++ b/examples/server_async.py
  @@ -313,4 +313,4 @@
   
   
   if __name__ == "__main__":
  -    asyncio.run(run_async_server("."), debug=True)
  +    asyncio.run(run_async_server(), debug=True)
  diff --git a/examples/server_sync.py b/examples/server_sync.py
  --- a/examples/server_sync.py
  +++ b/examples/server_sync.py
  @@ -313,5 +313,5 @@
   
   
   if __name__ == "__main__":
  -    server = run_sync_server(".")
  +    server = run_sync_server()
       server.shutdown()
  
  ```
  
golden_diff: diff --git a/cupy/logic/truth.py b/cupy/logic/truth.py
  --- a/cupy/logic/truth.py
  +++ b/cupy/logic/truth.py
  @@ -1,8 +1,11 @@
  +import cupy
  +
  +
   def all(a, axis=None, out=None, keepdims=False):
  -    # TODO(okuta): check type
  +    assert isinstance(a, cupy.ndarray)
       return a.all(axis=axis, out=out, keepdims=keepdims)
   
   
   def any(a, axis=None, out=None, keepdims=False):
  -    # TODO(okuta): check type
  +    assert isinstance(a, cupy.ndarray)
       return a.any(axis=axis, out=out, keepdims=keepdims)
  
verification_info: {"golden_diff": "diff --git a/cupy/logic/truth.py b/cupy/logic/truth.py\n--- a/cupy/logic/truth.py\n+++ b/cupy/logic/truth.py\n@@ -1,8 +1,11 @@\n+import cupy\n+\n+\n def all(a, axis=None, out=None, keepdims=False):\n-    # TODO(okuta): check type\n+    assert isinstance(a, cupy.ndarray)\n     return a.all(axis=axis, out=out, keepdims=keepdims)\n \n \n def any(a, axis=None, out=None, keepdims=False):\n-    # TODO(okuta): check type\n+    assert isinstance(a, cupy.ndarray)\n     return a.any(axis=axis, out=out, keepdims=keepdims)\n", "issue": "Different behaviour of argmax\nI found the behaviour of `argmax` is different between `numpy` and `cupy` if the array has `0` in its shape and `axis` argument is used. I don't know whether this behaviour is intended or not.\r\n\r\n```\r\nnp.empty((0, 1)).argmax(axis=1)  # array([], dtype=int64)\r\ncupy.empty((0, 1)).argmax(axis=1)\r\n---------------------------------------------------------------------------\r\nValueError                                Traceback (most recent call last)\r\n<ipython-input-9-a5737d72bcba> in <module>()\r\n----> 1 cupy.empty((0, 1)).argmax(axis=1)\r\n\r\ncupy/core/core.pyx in cupy.core.core.ndarray.argmax (cupy/core/core.cpp:17701)()\r\n\r\ncupy/core/core.pyx in cupy.core.core.ndarray.argmax (cupy/core/core.cpp:17556)()\r\n\r\ncupy/core/reduction.pxi in cupy.core.core.simple_reduction_function.__call__ (cupy/core/core.cpp:52697)()\r\n\r\nValueError: zero-size array to reduction operation cupy_argmax which has no identity\r\n```\r\n\r\nI used cupy 2.0.0a1.\n", "before_files": [{"content": "def all(a, axis=None, out=None, keepdims=False):\n    # TODO(okuta): check type\n    return a.all(axis=axis, out=out, keepdims=keepdims)\n\n\ndef any(a, axis=None, out=None, keepdims=False):\n    # TODO(okuta): check type\n    return a.any(axis=axis, out=out, keepdims=keepdims)\n", "path": "cupy/logic/truth.py"}], "after_files": [{"content": "import cupy\n\n\ndef all(a, axis=None, out=None, keepdims=False):\n    assert isinstance(a, cupy.ndarray)\n    return a.all(axis=axis, out=out, keepdims=keepdims)\n\n\ndef any(a, axis=None, out=None, keepdims=False):\n    assert isinstance(a, cupy.ndarray)\n    return a.any(axis=axis, out=out, keepdims=keepdims)\n", "path": "cupy/logic/truth.py"}]}