foo.cc: In function 'int main()':
foo.cc:16:12: error: unable to find numeric literal operator 'operator""x'
   16 |   cout<<80+3x;
      |            ^~
foo.cc:16:12: note: use '-fext-numeric-literals' to enable more built-in suffixes

[Hydro](https://hydro.ac)提供评测服务