View Compilation Error

0_0_33411778_9885.cpp: In function 'int main()':
0_0_33411778_9885.cpp:4:13: error: 'cin' was not declared in this scope
     a:while(cin>>x>>y && x||y)
             ^
0_0_33411778_9885.cpp:9:13: error: 'cout' was not declared in this scope
             cout<<"Sorry"<<endl;
             ^
0_0_33411778_9885.cpp:9:28: error: 'endl' was not declared in this scope
             cout<<"Sorry"<<endl;
                            ^
0_0_33411778_9885.cpp:12:9: error: 'cout' was not declared in this scope
         cout<<"OK"<<endl;
         ^
0_0_33411778_9885.cpp:12:21: error: 'endl' was not declared in this scope
         cout<<"OK"<<endl;
                     ^