CETTE Figure 1 typedef struct node { int num; struct node *next; } Node, *NodePtr; typedef struct { NodePtr top; } PeterType, *Peter; Peter P; // sample declaration of a Peter 1. 2. 3. 4. 5. 6. 7. int fun1(Peter Q) { if (empty(Q)) return INT_MIN; int hold = Q -> top -> num; NodePtr temp = Q -> top; Q -> top = Q -> top -> next; free(temp); return hold; } Given the above figure, type and function definitions, what describes the functionality of fun1? Pop Push Enqueue Dequeue None of these