/in/foo.c: In function 'main':
/in/foo.c:21:21: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
     value=(star[x][y+1])*4;
                    ~^~
/in/foo.c:21:19: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
     value=(star[x][y+1])*4;
           ~~~~~~~~^~~~~~