/in/foo.cc: In function 'void init()':
/in/foo.cc:20:15: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'long long int*' [-Wformat=]
  scanf("%d",&n);
               ^
/in/foo.cc: In function 'void work()':
/in/foo.cc:26:11: warning: unused variable 'ans' [-Wunused-variable]
  long int ans;
           ^~~