/in/foo.c: In function 'main':
/in/foo.c:6:10: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'float *' [-Wformat=]
  scanf("%d,%d,%d",&a,&b,&c);
          ^
/in/foo.c:6:13: warning: format '%d' expects argument of type 'int *', but argument 3 has type 'float *' [-Wformat=]
  scanf("%d,%d,%d",&a,&b,&c);
             ^
/in/foo.c:6:16: warning: format '%d' expects argument of type 'int *', but argument 4 has type 'float *' [-Wformat=]
  scanf("%d,%d,%d",&a,&b,&c);
                ^
/in/foo.c:10:12: warning: format '%d' expects argument of type 'int', but argument 2 has type 'double' [-Wformat=]
   printf("%d",(-b)/c);
            ^
/in/foo.c:28:24: error: 'i' undeclared (first use in this function)
   x1=(-b+sqrt(-delta))*i/(2*a);
                        ^
/in/foo.c:28:24: note: each undeclared identifier is reported only once for each function it appears in