foo.cc: In function 'int main()':
foo.cc:6:9: error: 'cin' was not declared in this scope
    6 |         cin >> n;
      |         ^~~
foo.cc:2:1: note: 'std::cin' is defined in header '<iostream>'; did you forget to '#include <iostream>'?
    1 | #include <stdio.h>
  +++ |+#include <iostream>
    2 | using namespace std;
foo.cc:8:26: error: 'sqrt' was not declared in this scope
    8 |         for(i = 2 ; i <= sqrt(n) ; i++){
      |                          ^~~~
foo.cc:19:9: error: 'cout' was not declared in this scope
   19 |         cout << s << end1;
      |         ^~~~
foo.cc:19:9: note: 'std::cout' is defined in header '<iostream>'; did you forget to '#include <iostream>'?
foo.cc:19:22: error: 'end1' was not declared in this scope
   19 |         cout << s << end1;
      |                      ^~~~

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