/in/foo.c: In function 'main':
/in/foo.c:7:11: error: stray '\357' in program
  double x1，x2;
           ^
/in/foo.c:7:12: error: stray '\274' in program
  double x1，x2;
            ^
/in/foo.c:7:13: error: stray '\214' in program
  double x1，x2;
             ^
/in/foo.c:7:14: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'x2'
  double x1，x2;
              ^~
/in/foo.c:7:14: error: 'x2' undeclared (first use in this function)
/in/foo.c:7:14: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:9:2: error: expected ';' before 'delta'
  delta=b*b-4*a*c
  ^~~~~
/in/foo.c:25:20: error: stray '\357' in program
    printf("无解")；
                    ^
/in/foo.c:25:21: error: stray '\274' in program
    printf("无解")；
                     ^
/in/foo.c:25:22: error: stray '\233' in program
    printf("无解")；
                      ^