Main.cc:1:1: error: 'include' does not name a type
include
^
Main.cc: In function 'int main()':
Main.cc:7:1: error: 'cin' was not declared in this scope
cin>>a>>b;
^
Main.cc:9:17: error: 'printf' was not declared in this scope
printf("%.5lf",c);
^