/in/foo.cc: In function 'int main()':
/in/foo.cc:63:7: warning: unused variable 'u' [-Wunused-variable]
   int u = q.front();
       ^
/in/foo.cc:96:18: warning: 'o.aa::i' may be used uninitialized in this function [-Wmaybe-uninitialized]
    he(o.i,a[i].i);
                  ^