foo.c:6:5: error: unknown type name 'Node'
    6 |     Node* next;
      |     ^~~~
foo.c:9:12: error: unknown type name 'Node'
    9 | int Search(Node* head, int x)
      |            ^~~~
foo.c:24:1: error: unknown type name 'Node'; use 'struct' keyword to refer to the type
   24 | Node* Insert(Node* head, int x)
      | ^~~~
      | struct 
foo.c:24:14: error: unknown type name 'Node'
   24 | Node* Insert(Node* head, int x)
      |              ^~~~
foo.c: In function 'main':
foo.c:49:5: error: unknown type name 'Node'; use 'struct' keyword to refer to the type
   49 |     Node* head = NULL;
      |     ^~~~
      |     struct 
foo.c:53:14: warning: implicit declaration of function 'Insert' [-Wimplicit-function-declaration]
   53 |         head=Insert(head, k);
      |              ^~~~~~
foo.c:53:13: warning: assignment to 'int *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
   53 |         head=Insert(head, k);
      |             ^
foo.c:57:12: warning: implicit declaration of function 'Search' [-Wimplicit-function-declaration]
   57 |     int m= Search(head, x);
      |            ^~~~~~

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