/in/foo.c: In function 'main':
/in/foo.c:63:8: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'long int *' [-Wformat=]
  scanf("%d",&n);
        ^
/in/foo.c:73:14: error: conflicting types for 'reverse16'
         char reverse16(char a);
              ^
/in/foo.c:14:6: note: previous definition of 'reverse16' was here
 char reverse16(char a[])
      ^