redo

src/main/java/puzzle/Mask.java

@@ -0,0 +1,12 @@
+package puzzle;
+
+public interface Mask {
+   
+   record Masker(long lo, long hi)
+           implements Mask { }
+   default Mask or(Mask o)         { return new Masker(o.lo() | lo(), o.hi() | hi()); }
+   default Mask and(Mask o) { return new Masker(o.lo() & lo(), o.hi() & hi()); }
+   
+   long hi();
+   long lo();
+}