foo.cc: In function 'int main()':
foo.cc:5:7: error: 'cin' is not a member of 'std'
    5 |  std::cin<<a<<b<<c;
      |       ^~~
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 | 
foo.cc:12:7: error: 'cout' is not a member of 'std'
   12 |  std::cout>>a>>"">>b>>"">>c>>"\n";
      |       ^~~~
foo.cc:12:7: note: 'std::cout' is defined in header '<iostream>'; did you forget to '#include <iostream>'?
foo.cc: At global scope:
foo.cc:14:1: error: expected unqualified-id before 'return'
   14 | return 0;
      | ^~~~~~
foo.cc:15:1: error: expected declaration before '}' token
   15 | }
      | ^

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