foo.c:16:1: error: unknown type name 'Node'
   16 | Node* findNode(N* head, int value)
      | ^~~~
foo.c: In function 'findNode':
foo.c:23:20: warning: returning 'N *' from a function with incompatible return type 'int *' [-Wincompatible-pointer-types]
   23 |             return current;
      |                    ^~~~~~~
foo.c: In function 'Unique':
foo.c:52:13: warning: implicit declaration of function 'findN'; did you mean 'findNode'? [-Wimplicit-function-declaration]
   52 |         if (findN(head, value) == NULL)
      |             ^~~~~
      |             findNode
foo.c:52:32: warning: comparison between pointer and integer
   52 |         if (findN(head, value) == NULL)
      |                                ^~

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