/in/foo.c: In function 'main':
/in/foo.c:8:5: error: expected '(' before 'xmin'
  if xmin>xmax
     ^~~~
/in/foo.c:8:5: warning: statement with no effect [-Wunused-value]
/in/foo.c:5:22: warning: unused variable 'b' [-Wunused-variable]
  int xmin,xmax,sum=0,b;
                      ^