/in/foo.cc: In function 'int add1(int, int)':
/in/foo.cc:37:71: warning: no return statement in function returning non-void [-Wreturn-type]
 int add1(int x,int y){to1[++cnt1]=y;nex1[cnt1]=head1[x];head1[x]=cnt1;}
                                                                       ^