View Compilation Error

0_0_33253842_10238.cpp: In function 'int main()':
0_0_33253842_10238.cpp:5:10: error: 'std::ios' has not been declared
     std::ios::sync_with_stdio(false);
          ^
0_0_33253842_10238.cpp:6:5: error: 'cin' is not a member of 'std'
     std::cin.tie(0);
     ^
0_0_33253842_10238.cpp:9:11: error: 'cin' was not declared in this scope
     while(cin >> n && n) {
           ^
0_0_33253842_10238.cpp:18:9: error: 'cout' was not declared in this scope
         cout << ans <<endl;
         ^
0_0_33253842_10238.cpp:18:23: error: 'endl' was not declared in this scope
         cout << ans <<endl;
                       ^