Compilare: user.cpp: In function ‘void build(int, int, int)’: user.cpp:6:11: warning: unused variable ‘first’ [-Wunused-variable] #define x first ^ user.cpp:40:27: note: in expansion of macro ‘x’ int i, u = 1, nr = 0, x, y; ^ user.cpp:7:11: warning: unused variable ‘second’ [-Wunused-variable] #define y second ^ user.cpp:40:30: note: in expansion of macro ‘y’ int i, u = 1, nr = 0, x, y; ^ user.cpp: In function ‘int query(int, int, int, std::pair<int, int>, std::pair<int, int>)’: user.cpp:115:1: warning: control reaches end of non-void function [-Wreturn-type] } ^