/in/foo.c: In function 'main':
/in/foo.c:8:12: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  { scanf("%s",&a[i]);
            ^
/in/foo.c:29:9: error: 'p' undeclared (first use in this function)
      if(p==j)
         ^
/in/foo.c:29:9: note: each undeclared identifier is reported only once for each function it appears in