/in/foo.c:3:6: error: conflicting types for 'remove'
 void remove(char s[],int si,int len);
      ^~~~~~
In file included from /in/foo.c:1:0:
/usr/include/stdio.h:180:12: note: previous declaration of 'remove' was here
 extern int remove (const char *__filename) __THROW;
            ^~~~~~
/in/foo.c: In function 'main':
/in/foo.c:7:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
  gets(s);
  ^~~~
In file included from /in/foo.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.c:8:10: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'char *' [-Wformat=]
  scanf("%d%d",&si,&len);
          ^
/in/foo.c:8:12: warning: format '%d' expects argument of type 'int *', but argument 3 has type 'char *' [-Wformat=]
  scanf("%d%d",&si,&len);
            ^
/in/foo.c: At top level:
/in/foo.c:13:6: error: conflicting types for 'remove'
 void remove(char s[],int si,int len)
      ^~~~~~
In file included from /in/foo.c:1:0:
/usr/include/stdio.h:180:12: note: previous declaration of 'remove' was here
 extern int remove (const char *__filename) __THROW;
            ^~~~~~