/in/foo.cc: In function 'int main()':
/in/foo.cc:9:11: warning: unused variable 'x' [-Wunused-variable]
     int n,x,y,z;
           ^
/in/foo.cc:9:13: warning: unused variable 'y' [-Wunused-variable]
     int n,x,y,z;
             ^
/in/foo.cc:9:15: warning: unused variable 'z' [-Wunused-variable]
     int n,x,y,z;
               ^