foo.cc: In function 'int search(Node)':
foo.cc:135:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
foo.cc: In function 'int main()':
foo.cc:141:18: warning: iteration 9 invokes undefined behavior [-Waggressive-loop-optimizations]
         hashs[i] = hashs[i-1] * i;
         ~~~~~~~~~^~~~~~~~~~~~~~~~
foo.cc:140:18: note: within this loop
     for(int i=1;i<11;i++){
                 ~^~~

自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。