/in/foo.c: In function 'main':
/in/foo.c:18:6: error: unknown type name 'in'
  for(in ti=0;i<=n+1;i++)
      ^~
/in/foo.c:18:14: error: 'i' undeclared (first use in this function)
  for(in ti=0;i<=n+1;i++)
              ^
/in/foo.c:18:14: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:18:9: warning: unused variable 'ti' [-Wunused-variable]
  for(in ti=0;i<=n+1;i++)
         ^~
/in/foo.c:34:6: error: expected expression before ')' token
      )
      ^