/in/foo.c: In function 'main':
/in/foo.c:8:2: warning: implicit declaration of function 'print' [-Wimplicit-function-declaration]
  print("请输入一元二次方程的系数 a, b, c：");
  ^~~~~
/in/foo.c:12:2: error: 'discriminant' undeclared (first use in this function)
  discriminant = b * b - 4 * a * c;
  ^~~~~~~~~~~~
/in/foo.c:12:2: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:21:2: error: 'reyurn' undeclared (first use in this function)
  reyurn 0;
  ^~~~~~
/in/foo.c:21:9: error: expected ';' before numeric constant
  reyurn 0;
         ^
/in/foo.c:5:8: warning: unused variable 'discriminamt' [-Wunused-variable]
  float discriminamt, root1,root2;
        ^~~~~~~~~~~~