C programming: why am I getting errors ?

#include

#include

#include

#include

#include

typedef char AirportCode[4];

typedef struct NodeTag

{

AirportCode Airport;

struct NodeTag *Link;

} NodeType;

NodeType *L, *M, *N;

void DeleteFirst(NodeType **L) {

NodeType *N;

if (*L != NULL) {

N= *L;

*L =(*L)>Link;

free(N); }

}