introduce bitloops

src/main/java/puzzle/Export.java

@@ -1,6 +1,7 @@
 package puzzle;
 
 import lombok.Getter;
+import lombok.NoArgsConstructor;
 import lombok.experimental.Accessors;
 import lombok.experimental.Delegate;
 import lombok.val;
@@ -339,13 +340,18 @@ public record Export() {
    
    @Getter
    @Accessors(fluent = true)
+   @NoArgsConstructor
    static final class IntListDTO {
       
       int[] data = new int[8];
       int   size = 0;
+      public IntListDTO(int size) {
+         data = new int[size];
+      }
       void add(int v) {
          if (size >= data.length) data = Arrays.copyOf(data, data.length * 2);
          data[size++] = v;
       }
+      int[] toArray() { return Arrays.copyOf(data, size); }
    }
 }

src/main/java/puzzle/SwedishGenerator.java

@@ -388,7 +388,8 @@ public class SwedishGenerator {
                   var r = rng.nextFloat();
                   //int idxInArray = rng.biasedIndexPow3(L - 1);
                   var arrIndex = (int) (r * r * r * (L - 1));
-                  var w        = entry.words[idxs[arrIndex]];
+                  var shardIdx = idxs[arrIndex];
+                  var w        = entry.words[shardIdx];
                   var lemIdx   = Lemma.unpackIndex(w);
                   if (Bit1029.get(used, lemIdx)) continue;
                   low = glo;
@@ -397,7 +398,7 @@ public class SwedishGenerator {
                   
                   Bit1029.set(used, lemIdx);
                   s.assign.w        = w;
-                  s.assign.shardIdx = arrIndex;
+                  s.assign.shardIdx = shardIdx;
                   if (backtrack(depth + 1)) return true;
                   s.assign.w = X;
                   Bit1029.clear(used, lemIdx);