View Compilation Error

0_0_17269192_22191.cpp: In function 'int main()':
0_0_17269192_22191.cpp:7:10: error: 'cin' was not declared in this scope
    while(cin>>n)
          ^
0_0_17269192_22191.cpp:14:8: error: 'cout' was not declared in this scope
        cout<<sum<<endl;
        ^
0_0_17269192_22191.cpp:14:19: error: 'endl' was not declared in this scope
        cout<<sum<<endl;
                   ^