quality.cpp:51:9: error: 'tree' does not name a type; did you mean 'free'?
51 | typedef tree<
| ^~~~
| free
quality.cpp: In function 'int rectangle(int, int, int, int, int (*)[3001])':
quality.cpp:62:3: error: 'ordered_set' was not declared in this scope
62 | ordered_set st;
| ^~~~~~~~~~~
quality.cpp:65:5: error: 'st' was not declared in this scope; did you mean 'tt'?
65 | st.insert({Q[b - 1][a - 1], t++});
| ^~
| tt
quality.cpp:65:33: error: 't' was not declared in this scope
65 | st.insert({Q[b - 1][a - 1], t++});
| ^
quality.cpp:70:5: error: 'st' was not declared in this scope; did you mean 'tt'?
70 | st.insert({Q[b - 1][a - 1], t++});
| ^~
| tt
quality.cpp:70:33: error: 't' was not declared in this scope
70 | st.insert({Q[b - 1][a - 1], t++});
| ^
quality.cpp:74:6: error: 'st' was not declared in this scope; did you mean 'tt'?
74 | st.erase(st.lowerbound({Q[b - 1][a - 1], 0}));
| ^~
| tt
quality.cpp:77:21: error: 'st' was not declared in this scope; did you mean 'tt'?
77 | res = min(res, (*st.find_by_order(h * w / 2)).first);
| ^~
| tt
quality.cpp:60:17: warning: unused variable 'tt' [-Wunused-variable]
60 | int res = 1e9, tt = 0;
| ^~