Compilare: user.cpp: In function ‘int main()’: user.cpp:28:27: warning: unused variable ‘xi’ [-Wunused-variable] long long n , x , y ,xi[501],yi[501],a=1,b=1,c; ^ user.cpp:28:35: warning: unused variable ‘yi’ [-Wunused-variable] long long n , x , y ,xi[501],yi[501],a=1,b=1,c; ^ user.cpp:28:47: warning: unused variable ‘b’ [-Wunused-variable] long long n , x , y ,xi[501],yi[501],a=1,b=1,c; ^ user.cpp:28:51: warning: variable ‘c’ set but not used [-Wunused-but-set-variable] long long n , x , y ,xi[501],yi[501],a=1,b=1,c; ^