Compilare: user.cpp: In function ‘int main()’: user.cpp:11:11: warning: unused variable ‘m’ [-Wunused-variable] int n,m,i,x,y,j,k,cost; ^ user.cpp:11:15: warning: unused variable ‘x’ [-Wunused-variable] int n,m,i,x,y,j,k,cost; ^ user.cpp:11:17: warning: unused variable ‘y’ [-Wunused-variable] int n,m,i,x,y,j,k,cost; ^ user.cpp:11:23: warning: unused variable ‘cost’ [-Wunused-variable] int n,m,i,x,y,j,k,cost; ^~~~