public readonly long MaxIndex; // long to support 20! or less
// ************************************************************************
public PermutationOuelletLexico(T[] sortedValues)
{
_sortedValues = sortedValues;
Result = new T[_sortedValues.Length];
MaxIndex = Factorial.GetFactorial(_sortedValues.Length);
}
// ************************************************************************
public static void ExecuteForEachPermutationMT(int[] sortedValues, Action <int[]> action)
{
int coreCount = Environment.ProcessorCount; // Hyper treading are taken into account (ex: on a 4 cores hyperthreaded = 8)
long itemsFactorial = Factorial.GetFactorial(sortedValues.Length);
long partCount = (long)Math.Ceiling((double)itemsFactorial / (double)coreCount);
long startIndex = 0;
var tasks = new List <Task>();
for (int coreIndex = 0; coreIndex < coreCount; coreIndex++)
{
long stopIndex = Math.Min(startIndex + partCount, itemsFactorial);
PermutationMixOuelletSaniSinghHuttunen mix = new PermutationMixOuelletSaniSinghHuttunen(sortedValues, startIndex, stopIndex);
Task task = Task.Run(() => mix.ExecuteForEachPermutation(action));
tasks.Add(task);
if (stopIndex == itemsFactorial)
{
break;
}
startIndex = startIndex + partCount;
}
Task.WaitAll(tasks.ToArray());
}
// ************************************************************************
/// <summary>
/// Sort Index is 0 based and should be less than MaxIndex. Otherwise you get an exception.
/// </summary>
/// <param name="sortIndex"></param>
/// <param name="result">Value is not used as inpu, only as output. Re-use buffer in order to save memory</param>
/// <returns></returns>
public void GetSortedValuesFor(long sortIndex)
{
int size = _sortedValues.Length;
if (sortIndex < 0)
{
throw new ArgumentException("sortIndex should greater or equal to 0.");
}
if (sortIndex >= MaxIndex)
{
throw new ArgumentException("sortIndex should less than factorial(the lenght of items)");
}
List <T> leftValues = new List <T>(_sortedValues);
long factorielLower = MaxIndex;
for (int index = 0; index < size; index++)
{
long factorielBigger = factorielLower;
factorielLower = Factorial.GetFactorial(size - index - 1); // factorielBigger / inverseIndex;
int resultItemIndex = (int)(sortIndex % factorielBigger / factorielLower);
T item = Result[index] = leftValues[resultItemIndex];
leftValues.Remove(item);
}
}
// ************************************************************************
/// <summary>
/// Sort Index is 0 based and should be less than MaxIndex. Otherwise you get an exception.
/// </summary>
/// <param name="sortIndex"></param>
/// <param name="result">Value is not used as inpu, only as output. Re-use buffer in order to save memory</param>
/// <returns></returns>
public void GetSortedValuesFor(long sortIndex)
{
int size = _sortedValues.Length;
if (sortIndex < 0)
{
throw new ArgumentException("sortIndex should greater or equal to 0.");
}
if (sortIndex >= MaxIndex)
{
throw new ArgumentException("sortIndex should less than factorial(the lenght of items)");
}
_positions[size - 1] = size - 1;
#if DEBUG
_positions[0] = -1;
_positions[1] = -1;
_positions[2] = -1;
if (sortIndex == 4)
{
Debug.Assert(false);
}
#endif
long factorielBigger = 1;
for (int index = 2; index <= size; index++)
{
long factorielLower = factorielBigger;
factorielBigger = Factorial.GetFactorial(index); // factorielBigger / inverseIndex;
int resultItemIndex = size - index + (int)(sortIndex % factorielBigger / factorielLower);
int temp = _positions[resultItemIndex];
_positions[resultItemIndex] = size - index;
if (resultItemIndex > size - index)
{
_positions[size - index] = temp;
}
Dump(_positions);
}
for (int index = 0; index < size; index++)
{
Result[_positions[index]] = _sortedValues[index];
}
Debug.Print("Result: ");
Dump(Result);
}
public readonly long MaxIndex; // long to support 20! or less
// ************************************************************************
public PermutationOuelletLexico3(T[] sortedValues)
{
if (sortedValues.Length <= 0)
{
throw new ArgumentException("sortedValues.Lenght should be greater than 0");
}
_sortedValues = sortedValues;
Result = new T[_sortedValues.Length];
_valueUsed = new bool[_sortedValues.Length];
MaxIndex = Factorial.GetFactorial(_sortedValues.Length);
}
// ************************************************************************
/// <summary>
/// Return the permutation relative to the index received.
/// Based on _sortedValues. Sort Index is 0 based and should be less than MaxIndex.
/// </summary>
/// <param name="sortIndex"></param>
/// <returns>The result is written in property: Result</returns>
public void GetValuesForIndex(long sortIndex)
{
int size = _sortedValues.Length;
if (sortIndex < 0)
{
throw new ArgumentException("sortIndex should be greater or equal to 0.");
}
if (sortIndex >= MaxIndex)
{
throw new ArgumentException("sortIndex should be less than factorial(the lenght of items)");
}
for (int n = 0; n < _valueUsed.Length; n++)
{
_valueUsed[n] = false;
}
long factorielLower = MaxIndex;
for (int index = 0; index < size; index++)
{
long factorielBigger = factorielLower;
factorielLower = Factorial.GetFactorial(size - index - 1); // factorielBigger / inverseIndex;
int resultItemIndex = (int)(sortIndex % factorielBigger / factorielLower);
int correctedResultItemIndex = 0;
for (;;)
{
if (!_valueUsed[correctedResultItemIndex])
{
resultItemIndex--;
if (resultItemIndex < 0)
{
break;
}
}
correctedResultItemIndex++;
}
Result[index] = _sortedValues[correctedResultItemIndex];
_valueUsed[correctedResultItemIndex] = true;
}
}
// ************************************************************************
/// <summary>
/// Calc the index, relative to the permutation received
/// as argument. Based on _sortedValues. Returned index is 0 based.
/// </summary>
/// <param name="values"></param>
/// <returns></returns>
public long GetIndexOfValues(T[] values)
{
int size = _sortedValues.Length;
long valuesIndex = 0;
List <T> valuesLeft = new List <T>(_sortedValues);
for (int index = 0; index < size; index++)
{
long indexFactorial = Factorial.GetFactorial(size - 1 - index);
T value = values[index];
int indexCorrected = valuesLeft.IndexOf(value);
valuesIndex = valuesIndex + (indexCorrected * indexFactorial);
valuesLeft.Remove(value);
}
return(valuesIndex);
}
// ************************************************************************
public PermutationMixOuelletSaniSinghHuttunen(int[] sortedValues, long indexFirst = -1, long indexLastExclusive = -1)
{
if (indexFirst == -1)
{
indexFirst = 0;
}
if (indexLastExclusive == -1)
{
indexLastExclusive = Factorial.GetFactorial(sortedValues.Length);
}
if (indexFirst >= indexLastExclusive)
{
throw new ArgumentException($"{nameof(indexFirst)} should be less than {nameof(indexLastExclusive)}");
}
_indexFirst = indexFirst;
_indexLastExclusive = indexLastExclusive;
_sortedValues = sortedValues;
}
// ************************************************************************
private int RunTest()
{
try
{
bool canRun = false;
lock (_lockObj)
{
if (!IsTestRunning)
{
canRun = true;
IsTestRunning = true;
}
}
if (!canRun)
{
MessageBox.Show("Already running test. Please try later.");
return(0);
}
Action <IEnumerable <int> > actionToDoOnPermutation = null;
Predicate <int[]> funcToDoOnPermutation = null; // Direct function for Sam to be fair (I do not want to add an additional indirection)
switch (EnumAction)
{
case EnumAction.Nothing_BestForPerformanceTest:
actionToDoOnPermutation = DoNothing;
funcToDoOnPermutation = DoNothingFunc;
break;
case EnumAction.CountItemWithBugWithMultithreadedCode:
actionToDoOnPermutation = IncreaseCount;
funcToDoOnPermutation = IncreaseCountFunc;
break;
case EnumAction.CountItemSafeInterlockedIncrement:
actionToDoOnPermutation = IncreaseCountSafeInterlockedIncrement;
funcToDoOnPermutation = IncreaseCountSafeInterlockedIncrementFunc;
break;
case EnumAction.CountItemSafeSpinLock:
actionToDoOnPermutation = IncreaseCountSafeSpinLock;
funcToDoOnPermutation = IncreaseCountSafeSpinLockFunc;
break;
case EnumAction.DumpPermutatedValuesAndCount:
actionToDoOnPermutation = DumpValues;
funcToDoOnPermutation = DumpValuesFunc;
if (CountOfElementsToPermute > 5)
{
var result = MessageBox.Show(
"The count of item to permute is greater than 5, it could take long to dump every items, are you sure you want to continue?",
"Warning",
MessageBoxButton.OKCancel);
if (result == MessageBoxResult.Cancel)
{
return(0);
}
}
break;
}
EnumAlgoPermutation algoPermutation = AlgoPermutation;
EnumAlgoPermutation algoPermutationActive;
_testCount++;
WriteLine($"Test {_testCount} started. Count {CountOfElementsToPermute}!. Action: {EnumUtil.GetEnumDescription(EnumAction)}.");
int[] values;
Stopwatch stopwatch = new Stopwatch();
// Eric OuelletHeap Algorithm
algoPermutationActive = EnumAlgoPermutation.OuelletHeap;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
PermutationOuellet.ForAllPermutation(values, (vals) =>
{
actionToDoOnPermutation?.Invoke(vals);
return(false);
});
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
// Eric OuelletHeap indexed Algorithm
algoPermutationActive = EnumAlgoPermutation.OuelletIndexed;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
var permutationGenerator = new PermutationOuelletLexico <int>(values);
// int[] result = new int[values.Length];
for (long i = 0; i < permutationGenerator.MaxIndex; i++)
{
permutationGenerator.GetSortedValuesFor(i);
{
actionToDoOnPermutation?.Invoke(permutationGenerator.Result);
}
}
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
// Eric OuelletHeap indexed Algorithm v2
algoPermutationActive = EnumAlgoPermutation.OuelletIndexedv2;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
var permutationGenerator = new PermutationOuelletLexico2 <int>(values);
// int[] result = new int[values.Length];
for (long i = 0; i < permutationGenerator.MaxIndex; i++)
{
permutationGenerator.GetSortedValuesFor(i);
{
actionToDoOnPermutation?.Invoke(permutationGenerator.Result);
}
}
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
// Eric OuelletHeap indexed Algorithm v3
algoPermutationActive = EnumAlgoPermutation.OuelletIndexedv3;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
var permutationGenerator = new PermutationOuelletLexico3 <int>(values);
// int[] result = new int[values.Length];
for (long i = 0; i < permutationGenerator.MaxIndex; i++)
{
permutationGenerator.GetValuesForIndex(i);
{
actionToDoOnPermutation?.Invoke(permutationGenerator.Result);
}
}
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
//// Eric OuelletHeap indexed Algorithm v4
//algoPermutationActive = EnumAlgoPermutation.OuelletIndexedv4;
//if (algoPermutation.HasFlag(algoPermutationActive))
//{
// _count = 0;
// values = GetValues();
// stopwatch.Reset();
// stopwatch.Start();
// var permutationGenerator = new PermutationOuelletLexico4<int>(values);
// // int[] result = new int[values.Length];
// for (int i = 0; i < permutationGenerator.MaxIndex; i++)
// {
// permutationGenerator.GetValuesForIndex(i);
// {
// actionDumpValues?.Invoke(permutationGenerator.Result);
// }
// }
// stopwatch.Stop();
// WriteResult(algoPermutationActive, stopwatch);
//}
algoPermutationActive = EnumAlgoPermutation.SaniSinghHuttunen;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
do
{
actionToDoOnPermutation?.Invoke(values);
}while (PermutationSaniSinghHuttunen.NextPermutation(values));
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
algoPermutationActive = EnumAlgoPermutation.OuelletIndexedv3HuttunenST;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
PermutationMixOuelletSaniSinghHuttunen mix = new PermutationMixOuelletSaniSinghHuttunen(values);
mix.ExecuteForEachPermutation(actionToDoOnPermutation);
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
algoPermutationActive = EnumAlgoPermutation.SimpleVar;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
do
{
actionToDoOnPermutation?.Invoke(values);
}while (!PermutationSimpleVar.NextPermutation(values));
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
algoPermutationActive = EnumAlgoPermutation.SimpleVarUnsafe;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
PermutationSimpleVarUnsafe permutations = new PermutationSimpleVarUnsafe();
permutations.Permutate(0, values.Length, (int[] vals) =>
{
actionToDoOnPermutation?.Invoke(vals);
});
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
// ErezRobinson Algorithm
algoPermutationActive = EnumAlgoPermutation.ErezRobinson;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
foreach (var vals in PermutationErezRobinson.QuickPerm(values))
{
actionToDoOnPermutation?.Invoke(vals);
}
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
algoPermutationActive = EnumAlgoPermutation.Sam;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
var pf = new PermutationFinder <int>();
pf.Evaluate(values, funcToDoOnPermutation);
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
algoPermutationActive = EnumAlgoPermutation.Ziezi;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
PermutationZiezi.EnumeratePermutation(values, actionToDoOnPermutation);
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
// Pengyang linq algorithm
algoPermutationActive = EnumAlgoPermutation.Pengyang;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
foreach (var vals in PermutationPengyang.GetPermutations(values, values.Length))
{
actionToDoOnPermutation?.Invoke(vals);
}
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
algoPermutationActive = EnumAlgoPermutation.OuelletIndexedMT;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
int[] result = new int[values.Length];
Parallel.For <PermutationOuelletLexico <int> >
(
0,
Factorial.GetFactorial(values.Length),
() => new PermutationOuelletLexico <int>(GetValues()),
(index, state, permutationOuellet) =>
{
permutationOuellet.GetSortedValuesFor(index);
actionToDoOnPermutation?.Invoke(permutationOuellet.Result);
return(permutationOuellet);
},
(permutationOuellet) => { }
);
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
algoPermutationActive = EnumAlgoPermutation.OuelletIndexedv3MT;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
int[] result = new int[values.Length];
Parallel.For <PermutationOuelletLexico3 <int> >
(
0,
Factorial.GetFactorial(values.Length),
() => new PermutationOuelletLexico3 <int>(GetValues()),
(index, state, permutationOuellet) =>
{
permutationOuellet.GetValuesForIndex(index);
actionToDoOnPermutation?.Invoke(permutationOuellet.Result);
return(permutationOuellet);
},
(permutationOuellet) => { }
);
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
algoPermutationActive = EnumAlgoPermutation.OuelletHuttunenMT;
if (algoPermutation.HasFlag(algoPermutationActive))
{
WriteIntro(algoPermutationActive);
_count = 0;
values = GetValues();
stopwatch.Reset();
stopwatch.Start();
PermutationMixOuelletSaniSinghHuttunen.ExecuteForEachPermutationMT(values, actionToDoOnPermutation);
stopwatch.Stop();
WriteResult(algoPermutationActive, stopwatch);
}
WriteLine("Test " + _testCount + " ended.");
WriteLine("---------------------------------------------------------------");
return(_count);
}
finally
{
IsTestRunning = false;
}
}