/in/foo.cc: In function 'int main()':
/in/foo.cc:21:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(ri i=1;i<=n;i++)
  ^~~
/in/foo.cc:23:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
   cout<<ans<<endl;
   ^~~~