/in/foo.cc: In function 'int main()':
/in/foo.cc:11:14: error: 'a' was not declared in this scope
   scanf("%d",a+i);
              ^
/in/foo.cc:12:7: error: 'a' was not declared in this scope
  sort(a,a+i);
       ^
/in/foo.cc:12:11: error: 'i' was not declared in this scope
  sort(a,a+i);
           ^
/in/foo.cc:12:12: error: 'sort' was not declared in this scope
  sort(a,a+i);
            ^