View Compilation Error

0_0_13761462_9311.cpp: In function 'int main(int, char**)':
0_0_13761462_9311.cpp:23:8: error: 'cin' was not declared in this scope
  while(cin>>n1>>n2)
        ^
0_0_13761462_9311.cpp:38:12: error: 'cout' was not declared in this scope
   if(flag) cout<<"possible"<<endl;
            ^
0_0_13761462_9311.cpp:38:30: error: 'endl' was not declared in this scope
   if(flag) cout<<"possible"<<endl;
                              ^
0_0_13761462_9311.cpp:39:8: error: 'cout' was not declared in this scope
   else cout<<"not possible"<<endl;
        ^
0_0_13761462_9311.cpp:39:30: error: 'endl' was not declared in this scope
   else cout<<"not possible"<<endl;
                              ^