/in/foo.cc: In function 'int Create_L(node*&, int)':
/in/foo.cc:12:17: warning: unused variable 'r' [-Wunused-variable]
  Linklist s,g,p,r;//指示指针
                 ^
/in/foo.cc:30:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int Sum_L(Linklist, int)':
/in/foo.cc:42:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int Print_L(Linklist)':
/in/foo.cc:52:1: warning: no return statement in function returning non-void [-Wreturn-type]
 } 
 ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:55:13: warning: unused variable 'w' [-Wunused-variable]
  Linklist L,w;
             ^
/in/foo.cc:56:10: warning: unused variable 'sum' [-Wunused-variable]
  int n,x,sum=0; 
          ^~~