public ModMathEvaluator AsInputTo(ModMathEvaluator wrap)
{
if (this.C != wrap.C)
{
throw new NotImplementedException();
}
return(new ModMathEvaluator((A * wrap.A).ModAbs(C), (wrap.A * B + wrap.B).ModAbs(C), C));
}
protected void RunScenario(string title, string input, long numCards, BigInteger targetPosition, long numShuffles)
{
RunScenario(title, () =>
{
var lines = input.Split(new[] { '\r', '\n' }, StringSplitOptions.RemoveEmptyEntries);
ModMathEvaluator DealNewStack()
{
return(new ModMathEvaluator(-1, -1, numCards));
//return (targetPosition) => (-1 * input(targetPosition) + -1).ModAbs(numCards);
}
ModMathEvaluator Cut(long count)
{
return(new ModMathEvaluator(1, count, numCards));
////if (count < 0)
////{
//// count = numCards + count;
////}
//return (prev) =>
//{
// var targetPosition = input(prev);
// return (1 * targetPosition + count).ModAbs(numCards);
// //if (targetPosition < numCards - count)
// //{
// // return targetPosition + count;
// //}
// //else
// //{
// // return targetPosition - (numCards - count);
// //}
//};
}
ModMathEvaluator DealWithIncrement(long increment)
{
long dealt = 0;
long startPosition = 0;
for (var i = 0; ; i++)
{
//Console.WriteLine($"T {targetPosition} {startPosition} {increment}");
if ((1 - startPosition) % increment == 0)
{
break;
}
dealt += (long)Math.Ceiling(((decimal)numCards - startPosition) / increment);
startPosition += increment - (numCards % increment);
startPosition %= increment;
}
//Console.WriteLine($"D {dealt} {targetPosition} {startPosition} {increment}");
dealt += (1 - startPosition) / increment;
var a = dealt;
return(new ModMathEvaluator(a, 0, numCards));
//return (prev) =>
//{
// var targetPosition = input(prev);
// checked
// {
// return (a * targetPosition + 0).ModAbs(numCards);
// }
// //long dealt = 0;
// //long startPosition = 0;
// //for (var i = 0; ; i++)
// //{
// // //Console.WriteLine($"T {targetPosition} {startPosition} {increment}");
// // if ((targetPosition - startPosition) % increment == 0)
// // {
// // break;
// // }
// // dealt += (long)Math.Ceiling(((decimal)numCards - startPosition) / increment);
// // startPosition += increment - (numCards % increment);
// // startPosition %= increment;
// //}
// ////Console.WriteLine($"D {dealt} {targetPosition} {startPosition} {increment}");
// //dealt += (targetPosition - startPosition) / increment;
// //return dealt;
//};
}
ModMathEvaluator Compute()
{
var result = new ModMathEvaluator(1, 0, numCards);
foreach (var line in lines.Reverse())
{
if (line.StartsWith("deal with increment"))
{
var x = long.Parse(line.Split(' ').Last());
result = result.AsInputTo(DealWithIncrement(x));
}
else if (line.StartsWith("cut"))
{
var x = long.Parse(line.Split(' ').Last());
result = result.AsInputTo(Cut(x));
}
else if (line.StartsWith("deal into new stack"))
{
result = result.AsInputTo(DealNewStack());
}
else
{
throw new NotImplementedException(line);
}
}
return(result);
}
var compute = Compute();
Console.WriteLine($"compute: {compute}");
Console.WriteLine(compute.Apply(targetPosition));
long shufflesComputeIs = 1;
while (numShuffles > 0)
{
Console.WriteLine($"Need to shuffle {numShuffles} more times");
Console.WriteLine($"Formula to shuffle {shufflesComputeIs} times is {compute}");
if (numShuffles % (shufflesComputeIs * 2) != 0)
{
Console.WriteLine($"Shuffling {shufflesComputeIs} times");
targetPosition = compute.Apply(targetPosition);
numShuffles -= shufflesComputeIs;
}
compute = compute.AsInputTo(compute);
shufflesComputeIs *= 2;
}
Console.WriteLine(targetPosition);
//var valForZero = Compute()(0);
//// magic number derived from excel magic
//Func<long, long> compute = (i) =>
//{
// {
// return (long)((((new BigInteger(valForZero) - i * 15432842991580)) % numCards + numCards) % numCards);
// //return ((((valForZero - i * 15432842991580)) % numCards + numCards) % numCards);
// }
//};
//var realCompute = Compute();
//Console.WriteLine(compute(1970) == realCompute(1970));
//Console.WriteLine(compute(12124) == realCompute(12124));
//Console.WriteLine(compute(312341) == realCompute(312341));
//Console.WriteLine(compute(1212434) == realCompute(1212434));
//Console.WriteLine(compute(12124322) == realCompute(12124322));
//Console.WriteLine(compute(121243344) == realCompute(121243344));
//Console.WriteLine(compute(1212233324) == realCompute(1212233324));
//Console.WriteLine(compute(34324534523) == realCompute(34324534523));
//Console.WriteLine(compute(123412341234) == realCompute(123412341234));
//var splitPoint = BinarySearch.GetMax(i => compute(i) == realCompute(i), 312341, 0, numCards);
////Console.WriteLine($"Split point: {splitPoint}");
////Console.WriteLine(compute(splitPoint - 1));
////Console.WriteLine(realCompute(splitPoint - 1));
////Console.WriteLine(compute(splitPoint));
////Console.WriteLine(realCompute(splitPoint));
////Console.WriteLine(compute(splitPoint + 1));
////Console.WriteLine(realCompute(splitPoint + 1));
//for (long i = -60; i < 50; i++)
//{
// Console.WriteLine($"{splitPoint + i}: {realCompute(splitPoint + i):00000000000000000} {compute(splitPoint + i):00000000000000000}");
//}
//var compute = Compute();
//var targetForMax = compute(numCards - 1);
//Console.WriteLine(targetForMax);
//compute = (i) =>
// ((targetForMax - (i - (numCards - 1)) * 15432842991580)) % 119315717514047;
//var initialTarget = targetPosition;
//for (long i = -60; i < 50; i++)
//{
// Console.WriteLine($"{targetPosition + i}: {compute(targetPosition + i):00000000000000000}");
//}
////Console.WriteLine(targetPosition);
//if (initialTarget == targetPosition)
//{
// Console.WriteLine($"Looped in {i}");
// return;
//}
//if (targetPosition < 10000000)
//{
// Console.WriteLine($"Got to {targetPosition} in {i}");
// return;
//}
//if (i % 10000 == 0)
//{
// Console.WriteLine($"Loop number {i}");
//}
//for (long i = 0; i < 50; i++)
//{
// Console.WriteLine($"{i:000}: {string.Join(" ", Enumerable.Range(11, 10).Select(i => $"{(targetPosition / i):000000000000000}"))}");
// targetPosition = Compute(targetPosition);
//}
////var compute = Compute();
//var initialTarget = targetPosition;
//var loopTarget = 101741582076661;
//////var loopTarget = 101741582076661 % 8828312 + 8828312 * 1;
////long loopTarget = 1234567 + 8828312;
////Console.WriteLine($"Target: {loopTarget}");
////targetPosition = initialTarget;
////for (long j = 0; j < loopTarget; j++)
////{
//// targetPosition = compute(targetPosition);
////}
////Console.WriteLine($"True result for {loopTarget}: {targetPosition}");
////targetPosition = initialTarget;
//var seen = new Dictionary<long, long>();
//for (long i = 1; ; i++)
//{
// targetPosition = compute(targetPosition);
// //Console.WriteLine(targetPosition);
// if (initialTarget == targetPosition)
// {
// Console.WriteLine($"Looped in {i}");
// return;
// }
// //if (targetPosition < 10000000)
// //{
// // Console.WriteLine($"Got to {targetPosition} in {i}");
// // return;
// //}
// if (i % 10000 == 0)
// {
// Console.WriteLine($"Loop number {i}");
// }
// if (seen.TryGetValue(targetPosition, out var v))
// {
// var loopLength = (i - v);
// Console.WriteLine($"Looped from {i} to {v} in {loopLength}");
// var toRun = (loopTarget - v) % loopLength + v;
// Console.WriteLine($"Simulating {toRun} times");
// //targetPosition = initialTarget;
// //for (long j = 0; j < toRun; j++)
// //{
// // targetPosition = compute(targetPosition);
// //}
// //Console.WriteLine(targetPosition);
// Console.WriteLine(seen.Single(i => i.Value == toRun).Key);
// return;
// }
// seen[targetPosition] = i;
//}
});
}
