foo.cc: In function 'int main()':
foo.cc:5:4: error: 'cout' was not declared in this scope
    5 |    cout<<"A"<<endl<<"AAA"<<endl<<"AAAAA"<<endl<<"AAAAAAA"<<endl;
      |    ^~~~
foo.cc:2:1: note: 'std::cout' is defined in header '<iostream>'; did you forget to '#include <iostream>'?
    1 | #include <stdio.h>
  +++ |+#include <iostream>
    2 | using namespace std;
foo.cc:5:15: error: 'endl' was not declared in this scope
    5 |    cout<<"A"<<endl<<"AAA"<<endl<<"AAAAA"<<endl<<"AAAAAAA"<<endl;
      |               ^~~~
foo.cc:2:1: note: 'std::endl' is defined in header '<ostream>'; did you forget to '#include <ostream>'?
    1 | #include <stdio.h>
  +++ |+#include <ostream>
    2 | using namespace std;

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