a←  1      + 0j1×1+⎕ct
   b← (1+⎕ct) + 0j1×1+⎕ct×2

   x←(a,b)[?1000⍴2]
   y←(a,b)[?1000⍴2]

   a=b
1
   x⍳y
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ...

   x {⍳⍨ ⍉cluster⍤1⍉ |⍵} HASH y
1 1 0 1 1 1 0 1 0 0 1 0 1 0 1 1 1 0 0 1 ...