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2 points by jsgrahamus 1658 days ago | link | parent

Here's a newer view. A number of variables (diagonals, result, row, total) get modified lower in the function. There must be a better way of updating those variables.


Thanks, Steve


  (def nqueens (board-size)
    (with (diagonals nil finished nil jsg 0 result '(0) row nil total 0)
	  (while (~ finished)
	         (let (diagonals2 result2 row2 total2)
		   (get-next-row board-size diagonals result total)
	           (if row2
		      (if (is (len result2) board-size)
			  (let (diagonals3 result3 total3)
			    (print-result diagonals2 result2 total2)
			      (= diagonals2 diagonals3)
			      (= result2 result3)
			      (= total2 total3))))
		        (= result2 (goto-next-column result2)))
		      (if (is (len result2) 1)
		        (= finished t)
		        (let (diagonals3 result3) 
		          (goto-previous-column diagonals2 result2)
			  (= diagonals2 diagonals3)
	  		  (= result2 result3))))
		   (= diagonals diagonals2)
		   (= result result2)
		   (= row row2)
		   (= total total2)))
	  (string "Number of results: " total)))

2 points by akkartik 1657 days ago | link

While I mull it over: do you have it working now?


2 points by jsgrahamus 1657 days ago | link

Yes, see below.