introduce bitloops

src/main/java/puzzle/SwedishGenerator.java

@@ -111,12 +111,13 @@ public record SwedishGenerator() {
          x = y;
          return y;
       }
-      public int randint2bit() { return nextU32() & 3; }
       public byte randint2bitByte() {
          var b = (byte) (nextU32() & 3);
-         /*if (b == 3) {
+       if (b == 3) {
             return 1;
-         }*/
+         }if (b == 4) {
+            return 2;
+         }
          return b;
       }
       public <T> T rand(T[] p)          { return p[(int) (((nextU32() & 0xFFFFFFFFL) % ((long) p.length /*- 0L*/ /*+ 1L*/)))]; }