From: Simon Tatham <anakin@pobox.com>
Date: Mon, 19 Feb 2007 19:38:00 +0000 (+0000)
Subject: Forgot to shuffle the num[] array! That was probably introducing
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?a=commitdiff_plain;h=aa6fb7507252dec76e2c30ebfdc76b0e366851d7;hp=d68ba4b21e11928fc256caca6d8836ac986848ad;p=sgt-puzzles.git

Forgot to shuffle the num[] array! That was probably introducing
some really subtle probabilistic bias in the generated latin squares.

[originally from svn r7302]
---

diff --git a/latin.c b/latin.c
index 22488a7..2d6ae74 100644
--- a/latin.c
+++ b/latin.c
@@ -1092,6 +1092,7 @@ digit *latin_generate(int o, random_state *rs)
 	for (j = 0; j < o; j++)
 	    col[j] = num[j] = j;
 	shuffle(col, j, sizeof(*col), rs);
+	shuffle(num, j, sizeof(*num), rs);
 	/* We need the num permutation in both forward and inverse forms. */
 	for (j = 0; j < o; j++)
 	    numinv[num[j]] = j;