Cache nearby elf positions

1 files changed, 16 insertions, 20 deletions

diff --git a/23.c b/23.c
index 99a3fb7..bc5291d 100644
--- a/23.c
+++ b/23.c
@@ -176,50 +176,46 @@ int
 trymove(char * buf, int cols, int rows, int round, int i, int j)
 {
 	static char const dirs[4] = { DIR_N, DIR_S, DIR_W, DIR_E };
+	int e_n, e_s, e_w, e_e, e_nw, e_ne, e_sw, e_se;
 	int d, dir;
 
 	if (!loc_elf(*pos(buf, cols, rows, i, j)))
 		// ???
 		return -1;
 
-	if (!loc_elf(*posd(buf, cols, rows, i, j, DIR_N))
-			&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_S))
-			&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_W))
-			&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_E))
-			&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_NW))
-			&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_NE))
-			&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_SW))
-			&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_SE)))
+	e_n = loc_elf(*posd(buf, cols, rows, i, j, DIR_N));
+	e_s = loc_elf(*posd(buf, cols, rows, i, j, DIR_S));
+	e_w = loc_elf(*posd(buf, cols, rows, i, j, DIR_W));
+	e_e = loc_elf(*posd(buf, cols, rows, i, j, DIR_E));
+	e_nw = loc_elf(*posd(buf, cols, rows, i, j, DIR_NW));
+	e_ne = loc_elf(*posd(buf, cols, rows, i, j, DIR_NE));
+	e_sw = loc_elf(*posd(buf, cols, rows, i, j, DIR_SW));
+	e_se = loc_elf(*posd(buf, cols, rows, i, j, DIR_SE));
+
+	if (!e_n && !e_s && !e_w && !e_e
+			&& !e_nw && !e_ne && !e_sw && !e_se)
 		// No elves nearby, do not move.
 		return 0;
 
 	for (d = 0, dir = 0; d < arrlen(dirs) && dir == 0; ++d) {
 		switch (dirs[(round + d) % 4]) {
 		case DIR_N:
-			if (!loc_elf(*posd(buf, cols, rows, i, j, DIR_N))
-					&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_NW))
-					&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_NE)))
+			if (!e_n && !e_nw && !e_ne)
 				dir = DIR_N;
 			break;
 
 		case DIR_S:
-			if (!loc_elf(*posd(buf, cols, rows, i, j, DIR_S))
-					&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_SW))
-					&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_SE)))
+			if (!e_s && !e_sw && !e_se)
 				dir = DIR_S;
 			break;
 
 		case DIR_W:
-			if (!loc_elf(*posd(buf, cols, rows, i, j, DIR_W))
-					&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_NW))
-					&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_SW)))
+			if (!e_w && !e_nw && !e_sw)
 				dir = DIR_W;
 			break;
 
 		case DIR_E:
-			if (!loc_elf(*posd(buf, cols, rows, i, j, DIR_E))
-					&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_NE))
-					&& !loc_elf(*posd(buf, cols, rows, i, j, DIR_SE)))
+			if (!e_e && !e_ne && !e_se)
 				dir = DIR_E;
 			break;