foo.cc: In function 'void DestroyList_L(LNode*&)':
foo.cc:26:14: warning: statement has no effect [-Wunused-value]
   26 |  for(L->prior==NULL; p; p=p->prior) //从后向前逐个销毁
      |              ^
foo.cc: In function 'int CreateList_L(LNode*&)':
foo.cc:84:6: warning: unused variable 'i' [-Wunused-variable]
   84 |  int i,n;
      |      ^
foo.cc: In function 'int Merg_L(LinkList, LinkList, LNode*&)':
foo.cc:135:17: warning: unused variable 'pc' [-Wunused-variable]
  135 |  LinkList pa,pb,pc,t;    //定义指向三个链表元素的指针
      |                 ^~
foo.cc: In function 'int CreateList_L(LNode*&)':
foo.cc:98:1: warning: control reaches end of non-void function [-Wreturn-type]
   98 | }
      | ^
foo.cc: In function 'int Merg_L(LinkList, LinkList, LNode*&)':
foo.cc:149:1: warning: control reaches end of non-void function [-Wreturn-type]
  149 | }
      | ^
foo.cc: In function 'int main()':
foo.cc:155:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  155 |  freopen("twlist.in","r",stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
foo.cc:156:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  156 |  freopen("twlist.out","w",stdout);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

Found 1 testcases.
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