View Compilation Error

0_0_39634010_107.cpp:2:20: error: missing terminating ' character
    2 | using namespace std'
      |                    ^
0_0_39634010_107.cpp:2:20: error: expected ';' before 'namespace'
    2 | using namespace std'
      |                    ^
      |                    ;
0_0_39634010_107.cpp: In function 'int main()':
0_0_39634010_107.cpp:13:7: error: 'sum' was not declared in this scope
   13 | cout<<sum<<endl;
      |       ^~~