View Compilation Error

0_0_37386031_2495.cpp: In function 'int main()':
0_0_37386031_2495.cpp:8:2: error: 'cin' was not declared in this scope
  cin>>N;
  ^
0_0_37386031_2495.cpp:25:4: error: 'cout' was not declared in this scope
    cout<<"Case "<<flag++<<": "<<num<<endl;
    ^
0_0_37386031_2495.cpp:25:38: error: 'endl' was not declared in this scope
    cout<<"Case "<<flag++<<": "<<num<<endl;
                                      ^
0_0_37386031_2495.cpp:28:4: error: 'cout' was not declared in this scope
    cout<<endl;
    ^
0_0_37386031_2495.cpp:28:10: error: 'endl' was not declared in this scope
    cout<<endl;
          ^