/in/foo.c: In function 'main':
/in/foo.c:32:16: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
         x1=(c/d*x%(b/d)+(b/d))%(b/d);
             ~~~^~
/in/foo.c:34:16: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
         y2=(c/d*y%(a/d)+(a/d))%(a/d);
             ~~~^~