C语言结构体数组指针运用

 struct NODE{

    
     int a;
    
     struct NODE *b;
    
     struct NODE *c;
    
 };
    
  
    
 struct NODE nodes[5] = {
    
     {5, nodes + 3, NULL},
    
     {15, nodes + 4, nodes + 3},
    
     {22, NULL, nodes + 4},
    
     {12, nodes + 1, nodes},
    
     {18, nodes + 2, nodes + 1}
    
 };
    
 (other declarations...)
    
 struct NODE *np = nodes + 2;
    
 struct NODE **npp = &nodes[1].b;