Compilare: main.cpp: In function 'int main()': main.cpp:24:12: warning: unused variable 'x' [-Wunused-variable] 24 | int n, x, y; | ^ main.cpp:24:15: warning: unused variable 'y' [-Wunused-variable] 24 | int n, x, y; | ^ main.cpp: In function 'int mex(std::vector<int>&)': main.cpp:14:35: warning: control reaches end of non-void function [-Wreturn-type] 14 | vector <bool> vis(n + 1, false); | ^