September 2017 Update

Task/Priority-queue/Axiom/priority-queue-3.axiom

@@ -1,3 +0,0 @@
-   [[5,"Make tea"], [4,"Feed cat"], [3,"Clear drains"], [2,"Tax return"],
-    [1,"Solve RC tasks"]]
-                                  Type: List(OrderedKeyEntry(Integer,String))

Task/Priority-queue/C/priority-queue-1.c

@@ -1,131 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-
-typedef struct { void * data; int pri; } q_elem_t;
-typedef struct { q_elem_t *buf; int n, alloc; } pri_queue_t, *pri_queue;
-
-#define priq_purge(q) (q)->n = 1
-#define priq_size(q) ((q)->n - 1)
-/* first element in array not used to simplify indices */
-pri_queue priq_new(int size)
-{
-  if (size < 4) size = 4;
-
-  pri_queue q = malloc(sizeof(pri_queue_t));
-  q->buf = malloc(sizeof(q_elem_t) * size);
-  q->alloc = size;
-  q->n = 1;
-
-  return q;
-}
-
-void priq_push(pri_queue q, void *data, int pri)
-{
-  q_elem_t *b;
-  int n, m;
-
-  if (q->n >= q->alloc) {
-    q->alloc *= 2;
-    b = q->buf = realloc(q->buf, sizeof(q_elem_t) * q->alloc);
-  } else
-    b = q->buf;
-
-  n = q->n++;
-  /* append at end, then up heap */
-  while ((m = n / 2) && pri < b[m].pri) {
-    b[n] = b[m];
-    n = m;
-  }
-  b[n].data = data;
-  b[n].pri = pri;
-}
-
-/* remove top item. returns 0 if empty. *pri can be null. */
-void * priq_pop(pri_queue q, int *pri)
-{
-  void *out;
-  if (q->n == 1) return 0;
-
-  q_elem_t *b = q->buf;
-
-  out = b[1].data;
-  if (pri) *pri = b[1].pri;
-
-  /* pull last item to top, then down heap. */
-  --q->n;
-
-  int n = 1, m;
-  while ((m = n * 2) < q->n) {
-    if (m + 1 < q->n && b[m].pri > b[m + 1].pri) m++;
-
-    if (b[q->n].pri <= b[m].pri) break;
-    b[n] = b[m];
-    n = m;
-  }
-
-  b[n] = b[q->n];
-  if (q->n < q->alloc / 2 && q->n >= 16)
-    q->buf = realloc(q->buf, (q->alloc /= 2) * sizeof(b[0]));
-
-  return out;
-}
-
-/* get the top element without removing it from queue */
-void* priq_top(pri_queue q, int *pri)
-{
-  if (q->n == 1) return 0;
-  if (pri) *pri = q->buf[1].pri;
-  return q->buf[1].data;
-}
-
-/* this is O(n log n), but probably not the best */
-void priq_combine(pri_queue q, pri_queue q2)
-{
-  int i;
-  q_elem_t *e = q2->buf + 1;
-
-  for (i = q2->n - 1; i >= 1; i--, e++)
-    priq_push(q, e->data, e->pri);
-  priq_purge(q2);
-}
-
-int main()
-{
-  int i, p;
-  const char *c, *tasks[] ={
-    "Clear drains", "Feed cat", "Make tea", "Solve RC tasks", "Tax return" };
-  int pri[] = { 3, 4, 5, 1, 2 };
-
-  /* make two queues */
-  pri_queue q = priq_new(0), q2 = priq_new(0);
-
-  /* push all 5 tasks into q */
-  for (i = 0; i < 5; i++)
-    priq_push(q, tasks[i], pri[i]);
-
-  /* pop them and print one by one */
-  while ((c = priq_pop(q, &p)))
-    printf("%d: %s\n", p, c);
-
-  /* put a million random tasks in each queue */
-  for (i = 0; i < 1 << 20; i++) {
-    p = rand() / ( RAND_MAX / 5 );
-    priq_push(q, tasks[p], pri[p]);
-
-    p = rand() / ( RAND_MAX / 5 );
-    priq_push(q2, tasks[p], pri[p]);
-  }
-
-  printf("\nq has %d items, q2 has %d items\n", priq_size(q), priq_size(q2));
-
-  /* merge q2 into q; q2 is empty */
-  priq_combine(q, q2);
-  printf("After merge, q has %d items, q2 has %d items\n",
-    priq_size(q), priq_size(q2));
-
-  /* pop q until it's empty */
-  for (i = 0; (c = priq_pop(q, 0)); i++);
-  printf("Popped %d items out of q\n", i);
-
-  return 0;
-}

Task/Priority-queue/C/priority-queue-2.c

@@ -1,9 +0,0 @@
-1: Solve RC tasks
-2: Tax return
-3: Clear drains
-4: Feed cat
-5: Make tea
-
-q has 1048576 items, q2 has 1048576 items
-After merge, q has 2097152 items, q2 has 0 items
-Popped 2097152 items out of q

Task/Priority-queue/Phix/priority-queue.phix

@@ -0,0 +1,54 @@
+integer tasklist = new_dict()
+
+procedure add_task(integer priority, string desc)
+    integer k = getd_index(priority,tasklist)
+    if k=0 then
+        putd(priority,{desc},tasklist)
+    else
+        sequence descs = getd_by_index(k,tasklist)
+        putd(priority,append(descs,desc),tasklist)
+    end if
+end procedure
+
+function list_task_visitor(integer priority, sequence descs, integer /*user_data*/)
+    ?{priority,descs}
+    return 1
+end function
+
+procedure list_tasks()
+    traverse_dict(routine_id("list_task_visitor"), 0, tasklist,true)
+end procedure
+
+function pop_task_visitor(integer priority, sequence descs, integer rid)
+    string desc = descs[1]
+    descs = descs[2..$]
+    if length(descs)=0 then
+        deld(priority,tasklist)
+    else
+        putd(priority,descs,tasklist)
+    end if
+    call_proc(rid,{priority,desc})
+    return 0
+end function
+
+procedure pop_task(integer rid)
+    if dict_size(tasklist)!=0 then
+        traverse_dict(routine_id("pop_task_visitor"), rid, tasklist,true)
+    end if
+end procedure
+
+add_task(3,"Clear drains")
+add_task(4,"Feed cat")
+add_task(5,"Make tea")
+add_task(1,"Solve RC tasks")
+add_task(2,"Tax return")
+
+procedure do_task(integer priority, string desc)
+    ?{priority,desc}
+end procedure
+
+list_tasks()
+?"==="
+pop_task(routine_id("do_task"))
+?"==="
+list_tasks()

Task/Priority-queue/Zkl/priority-queue-1.zkl

@@ -0,0 +1,20 @@
+class PQ{
+   fcn init(numLevels=10){  // 0..numLevels, bigger # == lower priorty
+      var [const] queue=(1).pump(numLevels+1,List.createLong(numLevels).write,L().copy);
+   }
+   fcn add(item,priorty){ queue[priorty].append(item); }
+   fcn peek{ if(q:=queue.filter1()) return(q[-1]);   Void }// -->Void if empty
+   fcn pop { if(q:=queue.filter1()) return(q.pop()); Void }// -->Void if empty
+   var [private] state=L();
+   fcn [private] next{ // iterate
+      qi,ii:=state;
+      foreach n in ([qi..queue.len()-1]){
+         q:=queue[n];
+	 if(ii>=q.len()) ii=0;
+	 else{ state.clear().append(n,ii+1); return(q[ii]) }
+      }
+      Void.Stop
+   }
+   fcn walker{ state.clear().append(0,0); Walker(next) } // iterator front end
+   fcn toString{ "PQ(%d) items".fmt(queue.reduce(fcn(sum,q){ sum+q.len() },0)) }
+}

Task/Priority-queue/Zkl/priority-queue-2.zkl

@@ -0,0 +1,13 @@
+pq:=PQ();
+foreach x in
+      (T("Clear drains",3, "Feed cat",4, "Make tea",5, "Solve RC tasks",1, "Tax return",2,
+         "Clean room",10,"Wash cat",10)){
+   pq.add(x,__xWalker.next())
+}
+pq.println();
+println("Number 1 thing to do: ",pq.peek());
+println("Top 2 things to do: ",pq.walker().walk(2));
+println("Do this next year: ",pq.walker().walk()[-1]);
+println("ToDo list:");
+foreach item in (pq){ item.println() }
+pq.println();