NB. {. -------------------------------------------------------------------

(scheck x{.$.y), (x=:_5 _10+?12 24) ({. -: {.&.$.) y=:          ?  12 24 3$2
(scheck x{.$.y), (x=:_5 _10+?12 24) ({. -: {.&.$.) y=:      _10+?  12 24 3$21
(scheck x{.$.y), (x=:_5 _10+?12 24) ({. -: {.&.$.) y=:    o._10+?  12 24 3$21
(scheck x{.$.y), (x=:_5 _10+?12 24) ({. -: {.&.$.) y=: j./o._10+?2 12 24 3$21

(scheck x{.$.y), (x=:0     ) ({. -: {.&.$.) y=:          ?  12 24 3$2
(scheck x{.$.y), (x=:3 2 0 ) ({. -: {.&.$.) y=:      _10+?  12 24 3$21
(scheck x{.$.y), (x=:2 0 3 ) ({. -: {.&.$.) y=:    o._10+?  12 24 3$21
(scheck x{.$.y), (x=:2 0   ) ({. -: {.&.$.) y=: j./o._10+?2 12 24 3$21

(scheck x{.$.y), (x=:_     ) ({. -: {.&.$.) y=:          ?  12 24 3$2
(scheck x{.$.y), (x=:3 2 _ ) ({. -: {.&.$.) y=:      _10+?  12 24 3$21
(scheck x{.$.y), (x=:2 _ 3 ) ({. -: {.&.$.) y=:    o._10+?  12 24 3$21
(scheck x{.$.y), (x=:2 _   ) ({. -: {.&.$.) y=: j./o._10+?2 12 24 3$21

(scheck x{.$.y), (x=:__    ) ({. -: {.&.$.) y=:          ?  12 24 3$2
(scheck x{.$.y), (x=:3 2 __) ({. -: {.&.$.) y=:      _10+?  12 24 3$21
(scheck x{.$.y), (x=:2 __ 3) ({. -: {.&.$.) y=:    o._10+?  12 24 3$21
(scheck x{.$.y), (x=:2 __  ) ({. -: {.&.$.) y=: j./o._10+?2 12 24 3$21

(x {.!.e y) -: $.^:_1 (x=: 10 20){. (3;e=:?100)$.$.y=:       2 3 5$1 
(x {.!.e y) -: $.^:_1 (x=: 10 20){. (3;e=:?100)$.$.y=:    1+?2 3 5$21
(x {.!.e y) -: $.^:_1 (x=: 10 20){. (3;e=:?100)$.$.y=: o. 1+?2 3 5$21
(x {.!.e y) -: $.^:_1 (x=: 10 20){. (3;e=:?100)$.$.y=: j./1+?2 3 5$21

(scheck x{."1$.y), (x=:12     -~?25     ) ({."1 -: {."1&.$.) y=:_10+?12 24 3$21
(scheck x{."2$.y), (x=:12 24  -~?25 49  ) ({."2 -: {."2&.$.) y=:_10+?12 24 3$21
(scheck x{."3$.y), (x=:12 24 3-~?25 49 7) ({."3 -: {."3&.$.) y=:_10+?12 24 3$21

x=: _1 2
y=: 10*i.2 3 4
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;0    )$.$.y
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;1    )$.$.y
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;2    )$.$.y
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;0 1  )$.$.y
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;0 2  )$.$.y
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;1 0  )$.$.y
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;1 2  )$.$.y
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;2 0  )$.$.y
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;2 1  )$.$.y
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;0 1 2)$.$.y
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;0 2 1)$.$.y
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;1 0 2)$.$.y
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;1 2 0)$.$.y
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;2 0 1)$.$.y
(scheck x{.t), (x{.y) -: $.^:_1 x{.t=: (2;2 1 0)$.$.y


4!:55 ;:'e t x y'