/in/foo.cc: In function 'int main()':
/in/foo.cc:8:14: error: 'n' was not declared in this scope
  scanf("%d",&n);
              ^
/in/foo.cc:11:21: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'int' [-Wformat=]
   scanf("%d",data[i]);
              ~~~~~~~^