/in/foo.cc: In function 'LL count(LL, LL)':
/in/foo.cc:27:13: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return ans-i;
             ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:27:13: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return ans-i;
             ^
/in/foo.cc:20:13: note: 'ans' was declared here
  LL l=i,r=n,ans,mid;
             ^~~
/in/foo.cc:48:9: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
   printf("%lld\n",ans);
   ~~~~~~^~~~~~~~~~~~~~