BSD 4_3_Net_2 development

[unix-history] / usr / src / lib / libg++ / grot / etc / ADT-examples / generic-q.cc

// From: "Douglas C. Schmidt" <schmidt@glacier.ics.uci.edu>
// Date: Sun, 25 Sep 88 16:19:35 -0700

#include <stream.h>
#include <ctype.h>
#include <String.h>
#include <generic.h>

#define queue(type) name2(type,queue)
#define list(type) name2(type,list)
#define queuedeclare(type)                     \
class queue(type) {                            \
  struct list(type) {                         \
     type item;                               \
     list(type) *next;                        \
  } *head;                                    \
  int sz;                                     \
public:                                        \
  queue(type)(void) {head = 0;sz = 0;}        \
  ~queue(type)(void) {                        \
     list(type) *temp;                        \
     while (head) {                           \
        temp = head;                          \
        head = head->next;                    \
        delete temp;                          \
     }                                        \
  }                                           \
  int  empty(void) {return(!head);}           \
  int  size(void) {return(sz);}               \
  void enqueue(type new_item);                \
  type front(void) {                          \
     return(head->next->item);                \
  }                                           \
  type dequeue(void);                         \
};

#define queueimplement(type)                   \
type queue(type)::dequeue(void) {              \
  if (head) {                                 \
     type temp = head->next->item;            \
     list(type) *temp_ptr;                    \
     if ((temp_ptr = head->next) == head) {   \
        head = 0;                             \
     }                                        \
     else {                                   \
        head->next = temp_ptr->next;          \
     }                                        \
     delete temp_ptr;                         \
     sz--;                                    \
     return(temp);                            \
  }                                           \
}                                              \
void queue(type)::enqueue(type new_item) {     \
  if (!head) {                                \
     head       = new list(type);             \
     head->item = new_item;                   \
     head->next = head;                       \
  }                                           \
  else {                                      \
     list(type) *temp_node  = new list(type); \
     temp_node->item  = new_item;             \
     temp_node->next  = head->next;           \
     head->next       = temp_node;            \
     head             = temp_node;            \
  }                                           \
  sz++;                                       \
}                                              \ 


queuedeclare(String);
queueimplement(String);
queuedeclare(double);
queueimplement(double);

main() {
  String Buf;
  queue(String) Q_String;
  queue(double) Q_double;

  while (cin >> Buf) {
     if (Buf.matches(RXalpha)) {
        Q_String.enqueue(String(Buf));
     }
     else if (Buf.matches(RXdouble)) {
        Q_double.enqueue(atof(Buf));
     }   
  }

  while (!Q_String.empty()) {
     cout << "Size = " << Q_String.size() << ",Item = " 
          << Q_String.front() << "\n";
     void(Q_String.dequeue());
  }

  while (!Q_double.empty()) {
     cout << "Size = " << Q_double.size() << ",Item = " 
          << Q_double.front() << "\n";
     void(Q_double.dequeue());
  }
  return (0);
}