pq: change priority tested

arnauddri · Jan 27, 2015 · 7bf01e7 · 7bf01e7
1 parent d75acd7
commit 7bf01e7
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Showing 2 changed files with 29 additions and 6 deletions.
diff --git a/data-structures/priority-queue/priority_queue.go b/data-structures/priority-queue/priority_queue.go
@@ -42,12 +42,12 @@ func (pq *PQ) Extract() (el Item) {
 	return pq.data.Extract().(Item)
 }
 
-func (pq *PQ) changePriority(el Item, priority int) {
+func (pq *PQ) ChangePriority(val interface{}, priority int) {
 	var storage = make([]Item, 0)
 
 	popped := pq.Extract()
 
-	for el != popped {
+	for val != popped.Value {
 		if pq.Len() == 0 {
 			panic("Item not found")
 		}
@@ -56,11 +56,12 @@ func (pq *PQ) changePriority(el Item, priority int) {
 		popped = pq.Extract()
 	}
 
-	el.Priority = priority
-	pq.data.Insert(el)
+	popped.Priority = priority
+	pq.data.Insert(popped)
 
-	for len(storage) > 0 {
+	for len(storage) > 1 {
 		pq.data.Insert(storage[0])
 		storage = storage[1 : len(storage)-1]
 	}
+	pq.data.Insert(storage[0])
 }
diff --git a/data-structures/priority-queue/priority_queue_test.go b/data-structures/priority-queue/priority_queue_test.go
@@ -5,7 +5,7 @@ import (
 	"testing"
 )
 
-func TestMinHeap(t *testing.T) {
+func TestPriorityQueue(t *testing.T) {
 	h := New()
 
 	h.Insert(*NewItem(8, 10))
@@ -31,3 +31,25 @@ func TestMinHeap(t *testing.T) {
 		}
 	}
 }
+
+func TestChangePriority(t *testing.T) {
+	h := New()
+
+	h.Insert(*NewItem(8, 10))
+	h.Insert(*NewItem(7, 11))
+	h.Insert(*NewItem(6, 12))
+	h.Insert(*NewItem(3, 13))
+	h.Insert(*NewItem(1, 14))
+	h.Insert(*NewItem(0, 15))
+	h.Insert(*NewItem(2, 16))
+	h.Insert(*NewItem(4, 17))
+	h.Insert(*NewItem(9, 18))
+	h.Insert(*NewItem(5, 19))
+
+	h.ChangePriority(8, 66)
+	popped := h.Extract()
+
+	if popped.Value != 8 {
+		t.Error()
+	}
+}