crooks

commit 1d9b390f1c02faeed11e3937674e8fb6a053e45c
parent b5fb0538080d7eea690fd5775ba206bf9f844c16
Author: Antoine Amarilli <a3nm@a3nm.net>
Date:   Sat,  7 Jun 2014 19:34:23 +0200

easy optims

Diffstat:
main.c
 | 
22
++++++++++------------

1 file changed, 10 insertions(+), 12 deletions(-)
diff --git a/main.c b/main.c
@@ -132,6 +132,8 @@ int upd_vio(int z, int x, int y, int v, int d) {
     new = A[z][x][y] | (1 << d);
   else
     new = A[z][x][y] & ~(1 << d);
+  if (old == new)
+    return 0; // nothing changed
   for (int p = 0; p < N; p++) {
     if (p != z) {
       val = ((new | (1 << 0)) == 7 ? 1 : 0) - ((old | (1 << 0)) == 7 ? 1 : 0);
@@ -336,8 +338,9 @@ int random_move() {
   int z = R[rook][0];
   int x = R[rook][1];
   int y = R[rook][2];
+  int delta = 0;
   G[z][x][y] = 0;
-  upd_atk_rm(rook);
+  delta += upd_atk_rm(rook);
   int nx, ny, nz;
   while (1) {
     nx = (rand() % N);
@@ -352,10 +355,8 @@ int random_move() {
   R[rook][0] = nz;
   R[rook][1] = nx;
   R[rook][2] = ny;
-  // recompute everything
-  // TODO: don't do this
-  upd_atk_add(rook);
-  return num_violations();
+  delta += upd_atk_add(rook);
+  return delta;
 }
 
 int position(int i) {
@@ -369,15 +370,11 @@ int position(int i) {
   for (int z = 0; z < N; z++)
     for (int x = 0; x < N; x++)
       for (int y = 0; y < N; y++)
-        if (!A[z][x][y] && !G[z][x][y])
+        if (!A[z][x][y] && !G[z][x][y]) {
           if (V[z][x][y] < best) {
             best = V[z][x][y];
+            nbs = 0;
           }
-  // best is now the minimal number of violations
-  for (int z = 0; z < N; z++)
-    for (int x = 0; x < N; x++)
-      for (int y = 0; y < N; y++)
-        if (!A[z][x][y] && !G[z][x][y])
           if (V[z][x][y] == best) {
             bs[nbs][0] = z;
             bs[nbs][1] = x;
@@ -385,6 +382,7 @@ int position(int i) {
             nbs++;
             if (debug) printf("%d %d %d is a fitting position\n", z, x, y);
           }
+        }
   // choose random cell among optimal ones
   int npos = rand() % nbs;
   int bz = bs[npos][0];
@@ -505,7 +503,7 @@ int main(int argc, char **argv) {
       if (useless > UBOUND) {
         // too many useless steps, do a random move
         useless = 0;
-        tot = random_move();
+        tot += random_move();
       }
     }
     // we have found a configuration for K rooks; display it