Compilare: user.cpp: In function ‘int main()’: user.cpp:73:23: warning: unused variable ‘i’ [-Wunused-variable] int priority = 0, i; ^ user.cpp:98:9: warning: unused variable ‘val’ [-Wunused-variable] int val = 0; ^ user.cpp:99:9: warning: unused variable ‘res’ [-Wunused-variable] int res; ^ user.cpp: In function ‘int calc(int, int, char)’: user.cpp:44:1: warning: control reaches end of non-void function [-Wreturn-type] } ^