/in/foo.cc: In function 'int main()':
/in/foo.cc:43:33: warning: ISO C++ says that these are ambiguous, even though the worst conversion for the first is better than the worst conversion for the second:
   43 |         Vector3 res1=(v1+v2-v3)*k;
      |                                 ^
/in/foo.cc:23:17: note: candidate 1: 'Vector3 Vector3::operator*(int) const'
   23 |         Vector3 operator*(int k) const
      |                 ^~~~~~~~
/in/foo.cc:18:17: note: candidate 2: 'Vector3 Vector3::operator*(const Vector3&)'
   18 |         Vector3 operator*(const Vector3& o) //叉积
      |                 ^~~~~~~~
/in/foo.cc:44:35: warning: ISO C++ says that these are ambiguous, even though the worst conversion for the first is better than the worst conversion for the second:
   44 |         Vector3 res2=((v1*v2)*v3)*k;
      |                                   ^
/in/foo.cc:23:17: note: candidate 1: 'Vector3 Vector3::operator*(int) const'
   23 |         Vector3 operator*(int k) const
      |                 ^~~~~~~~
/in/foo.cc:18:17: note: candidate 2: 'Vector3 Vector3::operator*(const Vector3&)'
   18 |         Vector3 operator*(const Vector3& o) //叉积
      |                 ^~~~~~~~