/in/foo.cc: In function 'int main()':
/in/foo.cc:5:14: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'int' [-Wformat=]
  scanf("%d",n);
              ^
/in/foo.cc:5:7: warning: 'n' is used uninitialized in this function [-Wuninitialized]
  scanf("%d",n);
  ~~~~~^~~~~~~~