NB. 8 Queens NB. English Version of Langlet 8 Queens wr =: 1!:2&2 rd =: 1!:1 NB. Diagonal Elements qx =: 3 : 0 i =. 0{y. j =. 1{y. x =. i.8 y =. (j-i) + x z =. (i+j) - x q =. (y =/ x) +. (z =/ x) ) NB. Vertcal and Horizontal Elements qvh =: 3 : 0 i =. 0{y. j =. 1{y. x =. i. 8 y =. 8#i z =. 8#j q =. (x =/ y) +. (z =/ x) ) queen =: 3 : 0 q =: 8 8$0 label_loop. wr q wr 'Enter i j:' ij =. ". rd 1 if. ij < 0 do. '*** end ***' return. end. qa =. (1) (