/in/foo.c: In function 'main':
/in/foo.c:10:9: error: 'else' without a previous 'if'
   10 |         else{
      |         ^~~~
/in/foo.c:12:29: error: 'm' undeclared (first use in this function)
   12 |                 x1=(-b+sqrt(m))/2*a;
      |                             ^
/in/foo.c:12:29: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:13:20: error: '\U0000ff08' undeclared (first use in this function)
   13 |                 x2=（-b-sqrt(m)）/2*a;
      |                    ^~
/in/foo.c:13:32: error: expected ';' before '\U0000ff09'
   13 |                 x2=（-b-sqrt(m)）/2*a;
      |                                ^~
      |                                ;
/in/foo.c:5:15: warning: variable 'd' set but not used [-Wunused-but-set-variable]
    5 |         float d;
      |               ^