foo.cc:3:17: error: 'sad' is not a namespace-name
 using namespace sad;
                 ^~~
foo.cc:3:20: error: expected namespace-name before ';' token
 using namespace sad;
                    ^
foo.cc: In function 'int main()':
foo.cc:9:2: error: 'cin' was not declared in this scope
  cin >> a >> b >> c;
  ^~~
foo.cc:9:2: note: suggested alternative:
In file included from foo.cc:1:0:
/usr/include/c++/7/iostream:60:18: note:   'std::cin'
   extern istream cin;  /// Linked to standard input
                  ^~~
foo.cc:11:1: error: expected primary-expression before '}' token
 }
 ^
foo.cc:7:15: warning: unused variable 'countt' [-Wunused-variable]
  int a, b, c, countt = 0;
               ^~~~~~
foo.cc: At global scope:
foo.cc:12:5: error: 'count' does not name a type
     count++;
     ^~~~~
foo.cc:13:1: error: expected unqualified-id before '{' token
 {
 ^
foo.cc:16:5: error: 'count' does not name a type
     count++;
     ^~~~~
foo.cc:17:1: error: expected unqualified-id before '{' token
 {
 ^
foo.cc:20:5: error: 'count' does not name a type
     count++;
     ^~~~~
foo.cc:21:1: error: expected unqualified-id before '{' token
 {
 ^

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