/in/foo.c: In function 'bubbleSort':
/in/foo.c:11:7: error: 'a' undeclared (first use in this function)
    if(a[j]>a[j+1])
       ^
/in/foo.c:11:7: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c: In function 'main':
/in/foo.c:23:10: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  scanf("%s");
          ^
/in/foo.c:25:18: error: expected expression before ']' token
  printf("%s",str[]);
                  ^
/in/foo.c:26:2: error: expected declaration or statement at end of input
  return 0;
  ^~~~~~