private IEnumerable <Edge> GetMinimumSpanningTreeEdgesBad(Dictionary <char, List <Edge> > g)
{
var h = new BinaryMinHeap <char>();
var vte = new Dictionary <char, Edge>();
// Fill Heap
var isFirst = true;
foreach (char key in g.Keys)
{
if (isFirst)
{
h.Add(new BinaryMinHeap <char> .Node {
Id = key, Weight = 0
});
isFirst = false;
}
else
{
h.Add(new BinaryMinHeap <char> .Node {
Id = key, Weight = int.MaxValue
});
}
}
var result = new List <Edge>();
while (h.HasItem())
{
var v = h.ExtractMinimum();
vte.TryGetValue(v.Id, out Edge ste);
if (ste != null)
{
result.Add(ste);
}
foreach (Edge e in g[v.Id])
{
char adj = e.V2;
if (!h.Contains(adj))
{
continue;
}
var node = h.GetNode(adj);
if (node.Weight > e.Weight)
{
node.Weight = e.Weight;
h.Decrease(node);
if (!vte.ContainsKey(node.Id))
{
vte.Add(node.Id, e);
}
vte[node.Id] = e;
}
}
}
return(result);
}
public void Add_and_remove_single()
{
_emptyIntMinHeap.Add(55);
Assert.IsTrue(_emptyIntMinHeap.Contains(55));
Assert.AreEqual(55, _emptyIntMinHeap.PeekMin());
Assert.AreEqual(1, _emptyIntMinHeap.Size);
Assert.AreEqual(55, _emptyIntMinHeap.RemoveMin());
Assert.AreEqual(0, _emptyIntMinHeap.Size);
Assert.IsFalse(_emptyIntMinHeap.Contains(55));
}
public void GivenKeepMin2Items_AddInReverseOrder_ShouldHold3Not4()
{
_intHeap = BinaryMinHeap <int> .CreateWithSizeLimit(new IntComparer(), 2);
Assert.AreEqual(0, _intHeap.Add(4));
Assert.AreEqual(0, _intHeap.Add(3));
Assert.AreEqual(0, _intHeap.Add(2));
// level 2 is now full, should discard on next add
Assert.AreEqual(4, _intHeap.Add(1));
}
public static IEnumerable <object[]> GetSampleBinaryHeap()
{
var sut = new BinaryMinHeap <char>();
var a = new BinaryMinHeap <char> .Node {
Id = 'a', Weight = -1
};
var b = new BinaryMinHeap <char> .Node {
Id = 'b', Weight = 2
};
var c = new BinaryMinHeap <char> .Node {
Id = 'c', Weight = 6
};
var d = new BinaryMinHeap <char> .Node {
Id = 'd', Weight = 4
};
var e = new BinaryMinHeap <char> .Node {
Id = 'e', Weight = 5
};
var f = new BinaryMinHeap <char> .Node {
Id = 'f', Weight = 7
};
var g = new BinaryMinHeap <char> .Node {
Id = 'g', Weight = 8
};
sut.Add(a);
sut.Add(b);
sut.Add(c);
sut.Add(d);
sut.Add(e);
sut.Add(f);
sut.Add(g);
yield return(new object[] { sut });
}
public static void CheckOrderInHeap_DecreasingOrder_ReturnsTrue()
{
BinaryMinHeap <long> minHeap = new BinaryMinHeap <long>(Comparer <long> .Default);
minHeap.Add(10);
minHeap.Add(9);
minHeap.Add(8);
minHeap.Add(7);
minHeap.Add(6);
minHeap.Add(5);
minHeap.Add(4);
minHeap.Add(3);
minHeap.Add(2);
minHeap.Add(1);
var isRightOrder = IsRightOrderInHeap <long>(minHeap);
Assert.True(isRightOrder);
}
public void CheckOrderInHeap_RandomOrder_ReturnsTrue()
{
BinaryMinHeap <long> minHeap = new BinaryMinHeap <long>(Comparer <long> .Default);
minHeap.Add(23);
minHeap.Add(42);
minHeap.Add(4);
minHeap.Add(16);
minHeap.Add(8);
minHeap.Add(1);
minHeap.Add(3);
minHeap.Add(100);
minHeap.Add(5);
minHeap.Add(7);
var isRightOrder = IsRightOrderInHeap <long>(minHeap);
Assert.IsTrue(isRightOrder);
}
public void ReplacingMinElementAndCheckingIfExtractedInSortedOrder()
{
var heap = new BinaryMinHeap <int>();
int maxHeapElement = 50000;
int minHeapElement = -50000;
int addedElements = 0;
//Adding every seventh number, then every fifth number,
//every third and at last all numbers
//NOTE: some items are added more than once
for (int i = 7; i > 0; i -= 2)
{
int el = minHeapElement;
while (el <= maxHeapElement)
{
heap.Add(el);
addedElements++;
el += i;
}
}
if (heap.Count != addedElements)
{
Assert.Fail();
}
heap.ReplaceMin(int.MaxValue);
heap.ReplaceMin(int.MaxValue);
heap.ReplaceMin(int.MaxValue);
int removedElements = 0;
var min = heap.PeekMin();
while (!heap.IsEmpty)
{
if (min > heap.PeekMin())
{
Assert.Fail();
}
min = heap.PopMin();
removedElements++;
}
Assert.IsTrue(heap.IsEmpty &&
heap.Count == 0 &&
addedElements == removedElements);
}
public void AddingElementsWithCustomComparerAndCheckingIfExtractedInSortedOrder()
{
//Creating heap with reversed comparer
var heap = new BinaryMinHeap <int>(Comparer <int> .Create(
(x, y) => y.CompareTo(x)));
int maxHeapElement = 50000;
int minHeapElement = -50000;
int addedElements = 0;
//Adding every seventh number, then every fifth number,
//every third and at last all numbers
//NOTE: some items are added more than once
for (int i = 7; i > 0; i -= 2)
{
int el = minHeapElement;
while (el <= maxHeapElement)
{
heap.Add(el);
addedElements++;
el += i;
}
}
if (heap.Count != addedElements)
{
Assert.Fail();
}
int removedElements = 0;
// because of the reversed comparer
var max = heap.PeekMin();
while (!heap.IsEmpty)
{
if (max < heap.PeekMin())
{
Assert.Fail();
}
max = heap.PopMin();
removedElements++;
}
Assert.IsTrue(heap.IsEmpty &&
heap.Count == 0 &&
addedElements == removedElements);
}
public void TestBinaryMinHeapDecrease()
{
var sut = new BinaryMinHeap <char>();
var a = new BinaryMinHeap <char> .Node {
Id = 'a', Weight = -1
};
var b = new BinaryMinHeap <char> .Node {
Id = 'b', Weight = 2
};
var c = new BinaryMinHeap <char> .Node {
Id = 'c', Weight = 6
};
var d = new BinaryMinHeap <char> .Node {
Id = 'd', Weight = 4
};
var e = new BinaryMinHeap <char> .Node {
Id = 'e', Weight = 5
};
var f = new BinaryMinHeap <char> .Node {
Id = 'f', Weight = 7
};
var g = new BinaryMinHeap <char> .Node {
Id = 'g', Weight = 8
};
sut.Add(a);
sut.Add(b);
sut.Add(c);
sut.Add(d);
sut.Add(e);
sut.Add(f);
sut.Add(g);
f.Weight = -2;
sut.Decrease(f);
g.Weight = -3;
sut.Decrease(g);
var expected = new[] { 'g', 'f', 'a', 'b', 'd', 'e', 'c' };
var actual = expected.Select(_ => sut.ExtractMinimum());
//foreach (BinaryMinHeap<char>.Node node in actual)
//{
// _output.WriteLine(node.ToString());
//}
Assert.True(expected.SequenceEqual(actual.Select(_ => _.Id)));
}
public void AddAndRemoveElements()
{
var r = new Random();
const int totalElements = 10000;
var elements = Enumerable.Range(1, totalElements).Select(x => r.Next(totalElements)).ToList();
var target = new BinaryMinHeap<int>();
foreach (var i in elements)
{
target.Add(i);
}
Assert.AreEqual(totalElements, target.Count);
elements.Sort();
for (var i = 0; i < totalElements; i++)
{
Assert.AreEqual(elements[i], target.RemoveMin());
}
}
public static void DoTest()
{
BinaryMinHeap <long> minHeap = new BinaryMinHeap <long>(Comparer <long> .Default);
minHeap.Add(23);
minHeap.Add(42);
minHeap.Add(4);
minHeap.Add(16);
minHeap.Add(8);
minHeap.Add(15);
minHeap.Add(9);
minHeap.Add(55);
minHeap.Add(0);
minHeap.Add(34);
minHeap.Add(12);
minHeap.Add(2);
minHeap.Add(93);
minHeap.Add(14);
minHeap.Add(27);
var array = minHeap.ToArray();
Assert.True(array.Length == minHeap.Count, "Wrong size.");
var list = minHeap.ToList();
Assert.True(list.Count == minHeap.Count, "Wrong size.");
array.HeapSortDescending();
var maxHeap = minHeap.ToMaxHeap();
Assert.True(maxHeap.Peek() == array[0], "Wrong maximum.");
}
public void ConvertingToBinaryMaxHeap()
{
var minHeap = new BinaryMinHeap <int>();
int maxHeapElement = 50000;
int minHeapElement = -50000;
int addedElements = 0;
//Adding every seventh number, then every fifth number,
//every third and at last all numbers
//NOTE: some items are added more than once
for (int i = 7; i > 0; i -= 2)
{
int el = minHeapElement;
while (el <= maxHeapElement)
{
minHeap.Add(el);
addedElements++;
el += i;
}
}
if (minHeap.Count != addedElements)
{
Assert.Fail();
}
// Binary min heap with reversed comparer. Have to be the same as the max heap
var reversedMinHeap = new BinaryMinHeap <int>(Comparer <int> .Create(
(x, y) => y.CompareTo(x)));
reversedMinHeap.Heapify(minHeap.ToArray());
var maxHeap = minHeap.ToMaxHeap();
if (maxHeap.Count != reversedMinHeap.Count)
{
Assert.Fail();
}
var max1 = reversedMinHeap.PeekMin();
var max2 = maxHeap.PeekMax();
int removedElements = 0;
while (!reversedMinHeap.IsEmpty && !maxHeap.IsEmpty)
{
if (max1 < reversedMinHeap.PeekMin())
{
Assert.Fail();
}
if (max2 < maxHeap.PeekMax())
{
Assert.Fail();
}
max1 = reversedMinHeap.PopMin();
max2 = maxHeap.PopMax();
removedElements++;
if (max1 != max2)
{
Assert.Fail();
}
}
Assert.IsTrue(reversedMinHeap.IsEmpty &&
maxHeap.IsEmpty &&
reversedMinHeap.Count == 0 &&
maxHeap.Count == 0 &&
addedElements == removedElements);
}
public void MergingTwoHeapsAndCheckingIfExtractedInSortedOrder()
{
var heap1 = new BinaryMinHeap <int>();
var heap2 = new BinaryMinHeap <int>();
int maxElementInFirstHeap = 100000;
int minElementInFirstHeap = 0;
int addedElementsInFirstHeap = 0;
//Adding every seventh number, then every fifth number,
//every third and at last all numbers
//NOTE: some items are added more than once
for (int i = 7; i > 0; i -= 2)
{
int el = minElementInFirstHeap;
while (el <= maxElementInFirstHeap)
{
heap1.Add(el);
addedElementsInFirstHeap++;
el += i;
}
}
int maxElementInSecondHeap = 50000;
int minElementInSecondHeap = -50000;
int addedElementsInSecondHeap = 0;
//Adding every seventh number, then every fifth number,
//every third and at last all numbers
//NOTE: some items are added more than once
for (int i = 7; i > 0; i -= 2)
{
int el = minElementInSecondHeap;
while (el <= maxElementInSecondHeap)
{
heap2.Add(el);
addedElementsInSecondHeap++;
el += i;
}
}
if (heap1.Count != addedElementsInFirstHeap)
{
Assert.Fail("first heap incorrect count");
}
if (heap2.Count != addedElementsInSecondHeap)
{
Assert.Fail("second heap incorrect count");
}
var oldHeap = new BinaryMinHeap <int>();
oldHeap.Heapify(heap1.ToArray());
heap1.Merge(heap2);
heap2.Merge(oldHeap);
int mergedHeapElements = addedElementsInFirstHeap + addedElementsInSecondHeap;
if (heap1.Count != mergedHeapElements)
{
Assert.Fail("merged first with second incorect count");
}
if (heap2.Count != mergedHeapElements)
{
Assert.Fail("merged second with first incorrect count");
}
var min1 = heap1.PeekMin();
var min2 = heap2.PeekMin();
if (min1 != min2)
{
Assert.Fail("merged heaps min element is different");
}
int removedElements = 0;
while (!heap1.IsEmpty && !heap2.IsEmpty)
{
if (min1 > heap1.PeekMin())
{
Assert.Fail();
}
if (min2 > heap2.PeekMin())
{
Assert.Fail();
}
min1 = heap1.PopMin();
min2 = heap2.PopMin();
removedElements++;
if (min1 != min2)
{
Assert.Fail("merged heaps min element is different");
}
}
Assert.IsTrue(heap1.IsEmpty &&
heap2.IsEmpty &&
heap1.Count == 0 &&
heap2.Count == 0 &&
mergedHeapElements == removedElements);
}
public void AddingAfterClearingHeap()
{
var heap = new BinaryMinHeap <int>();
int maxHeapElement = 50000;
int minHeapElement = -50000;
int addedElements = 0;
//Adding every seventh number, then every fifth number,
//every third and at last all numbers
//NOTE: some items are added more than once
for (int i = 7; i > 0; i -= 2)
{
int el = minHeapElement;
while (el <= maxHeapElement)
{
heap.Add(el);
addedElements++;
el += i;
}
}
if (heap.Count != addedElements)
{
Assert.Fail();
}
heap.Clear();
if (heap.Count != 0)
{
Assert.Fail();
}
addedElements = 0;
//Adding every seventh number, then every fifth number,
//every third and at last all numbers
//NOTE: some items are added more than once
for (int i = 7; i > 0; i -= 2)
{
int el = minHeapElement;
while (el < maxHeapElement)
{
heap.Add(el);
addedElements++;
el += i;
}
}
if (heap.Count != addedElements)
{
Assert.Fail();
}
int removedElements = 0;
var min = heap.PeekMin();
while (!heap.IsEmpty)
{
if (min > heap.PeekMin())
{
Assert.Fail();
}
min = heap.PopMin();
removedElements++;
}
Assert.IsTrue(heap.IsEmpty &&
heap.Count == 0 &&
addedElements == removedElements);
}
public static void DoTest ()
{
BinaryMinHeap<long> minHeap = new BinaryMinHeap<long> (Comparer<long>.Default);
minHeap.Add (23);
minHeap.Add (42);
minHeap.Add (4);
minHeap.Add (16);
minHeap.Add (8);
minHeap.Add (15);
minHeap.Add (9);
minHeap.Add (55);
minHeap.Add (0);
minHeap.Add (34);
minHeap.Add (12);
minHeap.Add (2);
minHeap.Add (93);
minHeap.Add (14);
minHeap.Add (27);
var array = minHeap.ToArray ();
Debug.Assert (array.Length == minHeap.Count, "Wrong size.");
var list = minHeap.ToList ();
Debug.Assert (list.Count == minHeap.Count, "Wrong size.");
array.HeapSortDescending();
var maxHeap = minHeap.ToMaxHeap ();
Debug.Assert (maxHeap.Peek() == array[0], "Wrong maximum.");
}