%%HP: T(3)A(R)F(.);
\<< 0 0 \-> eq v t p x
y
  \<< v PURGE 0 t
    FOR x eq
      IF x
      THEN 1 x
        FOR y v \.d
        NEXT
      END p v STO
EVAL v PURGE v p -
x ^ x ! / *
      IF x
      THEN +
      END
    NEXT COLCT
  \>>
\>>