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Optimize solutions by performing row/col analysis only

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Gabriel Tofvesson 2020-03-03 17:57:10 +01:00
parent ada2e58e47
commit 98de45e928
1 changed files with 128 additions and 8 deletions
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136
board.c
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@ -513,6 +513,123 @@ board_update_marks_by_excl (
else ERROR("Invalid parameters to function board_update_marks_by_excl()"); else ERROR("Invalid parameters to function board_update_marks_by_excl()");
} }
static bool
element_shares_value (struct board *board, board_pos x, board_pos y, element_value value)
{
struct board_element *elem = BOARD_ELEM (board, x, y);
return (elem->has_value && elem->value == value) || (! elem->has_value && (elem->potential & (1 << value) != 0));
}
static inline bool
field_is_potential (unsigned short field, element_value value)
{
return (field >> (value * 2)) & 3 < 2;
}
static inline void
field_invalidate (unsigned short *field, element_value value)
{
*field |= 2 << (value * 2);
}
static inline void
field_increment (unsigned short *field, element_value value)
{
if (field_is_potential (*field, value))
*field += (1 << (value * 2));
}
static void
field_populate_values(struct board *board, board_pos x, board_pos y, unsigned short *field)
{
struct board_element *elem = BOARD_ELEM (board, x, y);
if (elem->has_value)
{
field_invalidate (field, elem->value);
}
else
{
unsigned short potential = elem->potential;
element_value value = 0;
while (potential != 0)
{
if (potential & 1 == 1)
field_increment (field, value);
potential >>= 1;
++value;
}
}
}
static bool
board_update_marks_by_rows (struct board *board)
{
bool changed = false;
for (board_pos y = 0; y < 9; ++y)
{
unsigned short field = 0;
for (board_pos x = 0; x < 9; ++x)
field_populate_values (board, x, y, &field);
element_value value = 0;
while (field != 0)
{
if (field & 3 == 1)
{
for (board_pos x = 0; x < 9; ++x)
if (element_shares_value (board, x, y, value))
{
struct board_element *elem = BOARD_ELEM (board, x ,y);
elem->complexity = 1;
board->complexity = 1;
changed |= elem->potential != (elem->potential = (1 << value));
abort();
}
}
field >>= 2;
++value;
}
}
return changed;
}
static bool
board_update_marks_by_cols (struct board *board)
{
bool changed = false;
for (board_pos x = 0; x < 9; ++x)
{
unsigned short field = 0;
for (board_pos y = 0; y < 9; ++y)
field_populate_values (board, x, y, &field);
element_value value = 0;
while (field != 0)
{
if (field & 3 == 1)
{
for (board_pos y = 0; y < 9; ++y)
if (element_shares_value (board, x, y, value))
{
struct board_element *elem = BOARD_ELEM (board, x ,y);
elem->complexity = 1;
board->complexity = 1;
changed |= elem->potential != (elem->potential = (1 << value));
}
}
field >>= 2;
++value;
}
}
return changed;
}
void void
board_update_all_marks (struct board *board) board_update_all_marks (struct board *board)
@ -528,15 +645,18 @@ board_update_all_marks (struct board *board)
changed = false; changed = false;
/* Update marks by exclusion analysis */ /* Update marks by exclusion analysis */
for (board_pos y = 0; y < 9; ++y) // for (board_pos y = 0; y < 9; ++y)
for (board_pos x = 0; x < 9; ++x) // for (board_pos x = 0; x < 9; ++x)
if (! board_has_value (board, x, y)) // if (! board_has_value (board, x, y))
changed |= board_update_marks_by_excl (board, x, y); // changed |= board_update_marks_by_excl (board, x, y);
/* Update marks by quad potential analysis */ // /* Update marks by quad potential analysis */
for (board_pos y = 0; y < 9; y += 3) // for (board_pos y = 0; y < 9; y += 3)
for (board_pos x = 0; x < 9; x += 3) // for (board_pos x = 0; x < 9; x += 3)
changed |= board_update_marks_by_quad (board, x, y); // changed |= board_update_marks_by_quad (board, x, y);
changed |= board_update_marks_by_rows (board);
changed |= board_update_marks_by_cols (board);
} while (changed); } while (changed);
} }