Main.cc:2:1: error: ‘sing’ does not name a type; did you mean ‘uint’?
sing namespace std;
^~~~
uint
Main.cc: In function ‘int main()’:
Main.cc:4:5: error: ‘cout’ was not declared in this scope
cout<<"5050";
^~~~
Main.cc:4:5: note: suggested alternative:
In file included from Main.cc:1:0:
/usr/include/c++/7/iostream:61:18: note: ‘std::cout’
extern ostream cout; /// Linked to standard output
^~~~