View Compilation Error

0_0_39498757_10555.cpp:1:6: error: 'vector' in namespace 'std' does not name a template type
    1 | std::vector<u64> a(n + 1);
      |      ^~~~~~
0_0_39498757_10555.cpp:1:1: note: 'std::vector' is defined in header '<vector>'; did you forget to '#include <vector>'?
  +++ |+#include <vector>
    1 | std::vector<u64> a(n + 1);
0_0_39498757_10555.cpp:2:14: error: 'vector' in namespace 'std' does not name a template type
    2 |         std::vector<u64> ans(n + 1);
      |              ^~~~~~
0_0_39498757_10555.cpp:2:9: note: 'std::vector' is defined in header '<vector>'; did you forget to '#include <vector>'?
    2 |         std::vector<u64> ans(n + 1);
      |         ^~~