Compilare: user.cpp: In function ‘int main()’: user.cpp:211:13: warning: unused variable ‘j’ [-Wunused-variable] int n,i,j,t,nr,xf,xs,yf,ys; ^ user.cpp:211:20: warning: unused variable ‘xf’ [-Wunused-variable] int n,i,j,t,nr,xf,xs,yf,ys; ^ user.cpp:211:23: warning: unused variable ‘xs’ [-Wunused-variable] int n,i,j,t,nr,xf,xs,yf,ys; ^ user.cpp:211:26: warning: unused variable ‘yf’ [-Wunused-variable] int n,i,j,t,nr,xf,xs,yf,ys; ^ user.cpp:211:29: warning: unused variable ‘ys’ [-Wunused-variable] int n,i,j,t,nr,xf,xs,yf,ys; ^ user.cpp:225:15: warning: ‘nr’ may be used uninitialized in this function [-Wmaybe-uninitialized] g<<nr/2<<'\n'; ^