static void Main()
{
int nq = 8;
if (nq > 1)
{
for (var layout = new Permutation(nq); ; ++layout.Rank)
{
TOP : for (int x1 = 1; x1 < nq; ++x1)
{
for (int x2 = 0; x2 < x1; ++x2)
{
if (x1 - x2 - Math.Abs(layout[x2] - layout[x1]) == 0)
{
if (layout.Backtrack(x1) >= 0)
{
goto TOP;
}
else
{
return;
}
}
}
}
Console.WriteLine(String.Join(" ", Enumerable.Range(0, nq).Select(x => ((char)('a' + x)).ToString() + (layout[x] + 1))));
}
}
}
public void UnitPn_Backtrack1()
{
var pn1 = new Permutation(new int[] { 2, 1, 0 });
var pn2 = new Permutation(new int[] { 2, 1, 0 });
var pn3 = new Permutation(new int[] { 0, 1, 2 });
var pn4 = new Permutation(new int[] { 0, 2, 1 });
var pn5 = new Permutation(new int[] { 2, 3, 1, 0 });
var pn6 = new Permutation(new int[] { 1, 4, 0, 2, 3 });
int result1 = pn1.Backtrack(0);
int result2 = pn2.Backtrack(0);
int result3 = pn3.Backtrack(1);
int result4 = pn4.Backtrack(1);
int result5 = pn5.Backtrack(2);
int result6 = pn6.Backtrack(1);
Assert.AreEqual(-1, result1);
Assert.AreEqual(-1, result2);
Assert.AreEqual(1, result3);
Assert.AreEqual(0, result4);
Assert.AreEqual(0, result5);
Assert.AreEqual(0, result6);
Assert.AreEqual(new Permutation(new int[] { 0, 2, 1 }).Rank, pn3.Rank);
Assert.AreEqual(new Permutation(new int[] { 1, 0, 2 }).Rank, pn4.Rank);
Assert.AreEqual(new Permutation(new int[] { 3, 0, 1, 2 }).Rank, pn5.Rank);
Assert.AreEqual(new Permutation(new int[] { 2, 0, 1, 3, 4 }).Rank, pn6.Rank);
}
public void CrashPn_Backtrack_ArgumentOutOfRange2()
{
var pn = new Permutation(2);
pn.Backtrack(2);
}
public void CrashPn_Backtrack_InvalidOperation()
{
var pn = new Permutation(choices: 4, picks: 2);
pn.Backtrack(1);
}