combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:6:3: error: 'vector' was not declared in this scope
6 | vector<string>c;
| ^~~~~~
combo.cpp:2:1: note: 'std::vector' is defined in header '<vector>'; did you forget to '#include <vector>'?
1 | #include "combo.h"
+++ |+#include <vector>
2 | using namespace std;
combo.cpp:6:16: error: expected primary-expression before '>' token
6 | vector<string>c;
| ^
combo.cpp:6:17: error: 'c' was not declared in this scope
6 | vector<string>c;
| ^