View Compilation Error

0_0_16400666_19196.cpp: In function 'int main()':
0_0_16400666_19196.cpp:10:5: error: 'cin' was not declared in this scope
     cin>>t;
     ^
0_0_16400666_19196.cpp:19:23: error: 'cout' was not declared in this scope
         if(a[n-1]==1) cout<<"YES"<<endl;
                       ^
0_0_16400666_19196.cpp:19:36: error: 'endl' was not declared in this scope
         if(a[n-1]==1) cout<<"YES"<<endl;
                                    ^
0_0_16400666_19196.cpp:20:14: error: 'cout' was not declared in this scope
         else cout<<"NO"<<endl;
              ^
0_0_16400666_19196.cpp:20:26: error: 'endl' was not declared in this scope
         else cout<<"NO"<<endl;
                          ^