public static bool useBacktrackingAlgorithm(State state, int i, int j)
{
// state.showField();
depth++;
if (j == 9)//
{
j = 0;
i++;
if (i == 9)
{
return true;
}
}
if (state.field[i, j] != 0)
return (goodGuessSol(state, i, j + 1));
foreach (var val in state.candidates[i, j])
if (checkValid(i, j, val, state) == true)
{
state.field[i, j] = val;
if (goodGuessSol(state, i, j + 1) == true)
return true;
}
state.field[i, j] = 0;
return false;
}
public static bool checkValid(int i, int j, int val, State tmp)
{
for (int k = 0; k < 9; ++k)
if ((val == tmp.field[k, j]))
return false;
for (int k = 0; k < 9; ++k)
if ((val == tmp.field[i, k]))
return false;
int boxRowOffset = (i / 3) * 3;
int boxColOffset = (j / 3) * 3;
for (int k = 0; k < 3; ++k)
for (int m = 0; m < 3; ++m)
if ((val == tmp.field[boxRowOffset + k, boxColOffset + m]))
return false;
return true;
}