public bool HasSameCandidates(SudokuItem item)
{
bool rtVal = false;
if (item != null)
{
List <int> lst = new List <int>();
for (int k = 1; k < Candidates.Length; k++)
{
if (Candidates[k])
{
lst.Add(k);
}
}
for (int k = 1; k < item.Candidates.Length; k++)
{
if (item.Candidates[k])
{
if (lst.Contains(k))
{
lst.Remove(k);
}
else
{
return(rtVal);
}
}
}
rtVal = lst.Count == 0;
}
return(rtVal);
}
public Sudoku(int n)
{
this.n = n;
this.n2 = n * n;
Items = new SudokuItem[n2][];
for (int j = 0; j < Items.Length; j++)
{
Items[j] = new SudokuItem[n2];
for (int i = 0; i < Items[j].Length; i++)
{
Items[j][i] = new SudokuItem(this, n, i, j, 0);
}
}
Blocks = new SudokuBlock[n][];
for (int j = 0; j < Blocks.Length; j++)
{
Blocks[j] = new SudokuBlock[n];
for (int i = 0; i < Blocks[j].Length; i++)
{
Blocks[j][i] = new SudokuBlock(this, n, i, j);
}
}
for (int bj = 0; bj < Blocks.Length; bj++)
{
for (int bi = 0; bi < Blocks[bj].Length; bi++)
{
SudokuBlock block = Blocks[bj][bi];
for (int k = 0; k < block.Items.Length; k++)
{
int i = k % n;
int j = k / n;
block.Items[k] = Items[bj * n + j][bi * n + i];
}
}
}
Rows = new SudokuRow[n2];
for (int j = 0; j < n2; j++)
{
Rows[j] = new SudokuRow(this, n, j);
for (int i = 0; i < Rows[j].Items.Length; i++)
{
Rows[j].Items[i] = Items[j][i];
}
}
Columns = new SudokuColumn[n2];
for (int i = 0; i < n2; i++)
{
Columns[i] = new SudokuColumn(this, n, i);
for (int j = 0; j < Columns[i].Items.Length; j++)
{
Columns[i].Items[j] = Items[j][i];
}
}
}
public bool ClearCandidate(int c)
{
bool rtVal = false;
for (int i = 0; i < Items.Length; i++)
{
SudokuItem item = Items[i];
rtVal |= item.ClearCandidate(c);
}
return(rtVal);
}
private void btnGo_Click(object sender, EventArgs e)
{
try
{
int i = Convert.ToInt32(txtI.Text);
int j = Convert.ToInt32(txtJ.Text);
SudokuItem item = _sudoku.GetItem(i, j);
if (item != null)
{
txtCandidates.Text = string.Join(",", item.GetCandidateNumbers());
}
}
catch (Exception)
{
//
}
}
public bool TryHiddenSingles()
{
bool rtVal = false;
Dictionary <int, List <SudokuItem> > candidates = new Dictionary <int, List <SudokuItem> >();
for (int k = 1; k <= n2; k++)
{
candidates[k] = new List <SudokuItem>();
}
foreach (SudokuItem item in Items)
{
if (item.value > 0)
{
continue;
}
if (item.HasSingleCandidate(out int c))
{
item.SetValue(c);
rtVal = true;
return(rtVal);
}
for (int k = 1; k < item.Candidates.Length; k++)
{
if (item.Candidates[k] && !candidates[k].Contains(item))
{
candidates[k].Add(item);
}
}
}
foreach (var pair in candidates)
{
if (pair.Value.Count == 1)
{
rtVal = true;
SudokuItem item = pair.Value[0];
item.SetValue(pair.Key);
}
}
return(rtVal);
}
public bool ClearCandidates(IEnumerable <int> lst, IEnumerable <SudokuItem> excludeList)
{
bool rtVal = false;
for (int i = 0; i < Items.Length; i++)
{
SudokuItem item = Items[i];
if (item.value > 0)
{
continue;
}
if (excludeList == null)
{
rtVal |= item.ClearCandidates(lst);
}
else if (!excludeList.Contains(item))
{
rtVal |= item.ClearCandidates(lst);
}
}
return(rtVal);
}
public bool TryPointing()
{
bool rtVal = false;
// Row
for (int k = 0; k < n; k++)
{
List <SudokuItem> blockRow = new List <SudokuItem>();
HashSet <int> candidatesRow = new HashSet <int>();
for (int l = 0; l < n; l++)
{
SudokuItem item = Items[k * n + l];
blockRow.Add(item);
int[] numbers = item.GetCandidateNumbers();
foreach (int n in numbers)
{
candidatesRow.Add(n);
}
}
List <SudokuItem> blockRestItems = Items.Except(blockRow).ToList();
HashSet <int> candidatesRestItems = new HashSet <int>();
foreach (SudokuItem item in blockRestItems)
{
int[] numbers = item.GetCandidateNumbers();
foreach (int n in numbers)
{
candidatesRestItems.Add(n);
}
}
IEnumerable <int> result = candidatesRow.Except(candidatesRestItems);
if (result.Any())
{
SudokuRow row = Sudoku.Rows[blockRow[0].j];
row.ClearCandidates(result, blockRow);
}
}
// Column
for (int k = 0; k < n; k++)
{
List <SudokuItem> blockCol = new List <SudokuItem>();
HashSet <int> candidatesCol = new HashSet <int>();
for (int l = 0; l < n; l++)
{
SudokuItem item = Items[k + l * n];
blockCol.Add(item);
int[] numbers = item.GetCandidateNumbers();
foreach (int n in numbers)
{
candidatesCol.Add(n);
}
}
List <SudokuItem> blockRestItems = Items.Except(blockCol).ToList();
HashSet <int> candidatesRestItems = new HashSet <int>();
foreach (SudokuItem item in blockRestItems)
{
int[] numbers = item.GetCandidateNumbers();
foreach (int n in numbers)
{
candidatesRestItems.Add(n);
}
}
IEnumerable <int> result = candidatesCol.Except(candidatesRestItems);
if (result.Any())
{
SudokuColumn col = Sudoku.Columns[blockCol[0].i];
col.ClearCandidates(result, blockCol);
}
}
return(rtVal);
}