stellar

Index of the least significant bit function

1 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/ src/engine.c b/ src/engine.c

@@ -36,6 +36,13 @@ static inline int bit_count(U64 bitboard) { return count; }

static inline int bit_lsb_index(U64 bitboard) {

if (!bitboard)

return -1;

return bit_count((bitboard & -bitboard) - 1);

}

// squares // clang-format off enum enumSquare {

@@ -49,7 +56,7 @@ enum enumSquare { a8, b8, c8, d8, e8, f8, g8, h8 };

char squares[][3]={

const char *square_to_coordinates[]={

"a1", "b1", "c1", "d1", "e1", "f1", "g1", "h1", "a2", "b2", "c2", "d2", "e2", "f2", "g2", "h2", "a3", "b3", "c3", "d3", "e3", "f3", "g3", "h3",

@@ -246,9 +253,9 @@ int main(void) { bit_set(block, d4); bit_set(block, d5);

for (int square = 0; square < 64; square++)

bitboard_print(mask_bishop_attacks(square));

printf("%d\n", bit_count(block));

bitboard_print(block);

bitboard_print((block & -block) - 1);

int cord = bit_lsb_index(block);

printf("%d: %s\n", cord, square_to_coordinates[cord]);

return 0; }