Main.cc: In function 'int main()':
Main.cc:8:4: error: 'doublb' was not declared in this scope
doublb pi=3.1415926,n;
^
Main.cc:9:9: error: 'n' was not declared in this scope
cin>>n;
^
Main.cc:10:25: error: 'pi' was not declared in this scope
printf("%.4lf",4.0/3*pi*n*n*n);
^