View Compilation Error

0_0_26252770_4009.cpp: In function 'int main()':
0_0_26252770_4009.cpp:7:8: error: 'cin' was not declared in this scope
  while(cin>>arr)
        ^
0_0_26252770_4009.cpp:21:4: error: 'cout' was not declared in this scope
    cout<<arr[i];
    ^
0_0_26252770_4009.cpp:27:3: error: 'cout' was not declared in this scope
   cout<<endl;
   ^
0_0_26252770_4009.cpp:27:9: error: 'endl' was not declared in this scope
   cout<<endl;
         ^