A.if(a) printf("%d\n",x);else printf("%d\n",y);
B.if(a==0) printf("%d\n",y);else pfintf("%d\n",x);
C.if(a!=0) printf("%d\n",x);else printf("%d\n",y);
D.if(a==0) printf("%d\n",x);else printf("%d\n",y);