foo.cc: In function ‘int main()’:
foo.cc:7:19: error: unable to find numeric literal operator ‘operator""；’
    7 |         double PI=3.14159；
      |                   ^~~~~~~~~
foo.cc:7:19: note: use ‘-fext-numeric-literals’ to enable more built-in suffixes
foo.cc:9:9: error: ‘cout’ was not declared in this scope; did you mean ‘std::cout’?
    9 |         cout<<ceil(20000/(PI*r*r*h));
      |         ^~~~
      |         std::cout
iostream:63:18: note: ‘std::cout’ declared here
foo.cc:9:15: error: ‘ceil’ was not declared in this scope
    9 |         cout<<ceil(20000/(PI*r*r*h));
      |               ^~~~
foo.cc:10:9: error: ‘retuurn’ was not declared in this scope
   10 |         retuurn 0;
      |         ^~~~~~~